T>;     hook  is  DUE  on  the  last  date  stamped  below 


I 

fL 


ANGELES,  CALIFOK        ' 


BACTERIOLOGY  FOR  NURSES 


THE  MACMILLAN   COMPANY 


MACMILLAN  &  CO  ,  LIMITED 

LONDON   •    BOMBAY   •    CALCUTTA 
MELBOURNE 

THE  MACMILLAN  CO.  OF  CANADA,  LTD. 


BACTERIOLOGY    FOR   NURSES 


BT 


ISABEL   McISAAC,   R.N. 

AUTHOR  OF  "PRIMARY  NURSING  TECHNIQUE,"  "HYGIKNI 
FOR  NURSES,"  "HYGIENE  FOR  THE  USE  OF 

PUBLIC   SCHOOLS" 


SECOND  EDITION.    REVISED 


Nefa  gorfc 
THE   MACMILLAN   COMPANY 

1918 


All  right*  reserved 


COPYRIGHT,  1909,  1914, 
BY  THE  M  ACM  ILL  AN   COMPANY. 


Set  up  and  electrotyped      Published  November,  1909.     Reprinted 
October,  ign;  September,  1912:  July,  1913. 

Revised  Edition,  May,  October,  1914;  July,  1915; 
August,  October,  1916;  March,  1917. 


Norfoooli  $r«B 

J.  8.  Cashing  Co.  —  Berwick  A  Smith  Co. 
Norwood,  Mass.,  U.S.A. 


TTO 
EUPHEMIA 

SISTER  AND  COMRADE 


TEACHERS'   PREFACE 

IN  arranging  these  chapters  on  bacteriology  for 
the  use  of  pupil  nurses,  no  attempt  has  been  made 
to  do  more  than  to  endeavor  to  bring  the  essentials 
of  an  enormous  subject  into  a  practical  arrange- 
ment, which  will  serve  to  introduce  young  nurses 
to  one  of  the  most  important  phases  of  nursing; 
viz.,  the  prevention  of  infection. 

The  suggested  schedule  for  laboratory  work  was 
compiled  from  several  outlines  which  are  in  use  in 
different  schools  for  nurses,  the  courses  varying 
from  five  exercises  of  one  hour  each,  to  twenty 
exercises  of  two  hours  each ;  one  seemingly  inade- 
quate and  the  other  requiring  more  time  than  is 
feasible  in  the  majority  of  schools.  This  work 
should  not  be  attempted  in  the  classroom,  but 
should  be  done  in  a  well-equipped  laboratory  under 
the  direction  of  a  bacteriologist.  The  class  work 
may  easily  be  done  by  the  nurse  teachers,  but  they 
should  not  attempt  the  laboratory  exercises  except 
after  extended  bacteriological  work. 

The  schedule  should  not  be  regarded  as  inflex- 
ible, as  numerous  opportunities  for  the  observation 
of  material  from  well-known  cases  in  the  wards 

vii 


Vlll  PREFACE 

will  arise,  and  their  use  serve  to  impress  more 
strongly  upon  the  pupils  the  manifestations  of  par- 
ticular infections.  Neither  should  the  arrange- 
ment of  the  chapters  be  immovable  ;  the  laboratory 
exercises  and  class  work  should  go  hand  in  hand. 


SCHEDULE  FOR   TWELVE   LABORATORY 
EXERCISES  OF  TWO-HOUR  PERIODS 

Exercise     I.     Washing,  plugging,  and  sterilizing  glassware. 
Exercise    II.     Making  of  media. 
Exercise  III.     Technique  of : 

Inoculation  of  media. 

Preparation  of  plates. 

Hanging  drop. 

Use  of  microscope. 
Exercise    IV.    Making  and  microscopical  examination  of  stained 

preparations. 
Exercise     V.    Observation  of  bacilli : 

Spore-bearing. 

B.  subtilis. 

B.  chromogenic,  etc. 
Pathogenic : 

B.  coli  communis. 

B.  typhosus. 

B,  tuberculosis. 

B.  diphtheria. 

Demonstration  of  Widal's  test. 
Exercise    VI.     Observation  of  pathogenic  micrococci : 

Staphylococci. 

Streptococci. 

Pneumococcus. 

Gonococcus. 
Spirilla: 

S.  cholerce. 

Treponema  pallidum. 

Exercise    VII.     Demonstration  of  anaerobic  cultures. 
Exercise  VIII.     Bacteriological  examination  of  water;  from  five 
or  six  sources  and  after  sterilization. 


X  SCHEDULE 

Exercise     IX.     Examination   of    air   and  dust;    from    hospital 

wards,  dwellings,  and  the  street. 
Exercise       X.     Examination  of  cultures  from  hands,  and  from 

rubber  gloves ;  before  and  after  sterilization. 
Exercise     XI.     Examination  of  milk ;  from  the  hospital  supply, 

from  outside  sources,  and  after  pasteurization. 
Exercise   XII.     Examination  of  cultures  from  surgical  dressings 

and  suture  material. 


FOR  NURSES'   REFERENCE   LIBRARY 

Manual   of  Bacteriology,  by  Robert  Muir,  M.A.,  M.D.,  F.R.C.P. 

Ed.,  and  James  Ritchie,  M.A.,  M.D.,  B.Sc.     [Macmillan.] 
Practical  Bacteriology,  by  Edwin  O.  Jordan,  Ph.D.    [Saunders.] 
Hygiene  of  Transmissible  Diseases,  by  A.  C.  Abbott,  M.  D.  [Saunders.] 
A  Laboratory  Guide  in  Bacteriology,  by  Paul  G.  Heinemann,  Sc.B. 

[University  of  Chicago  Press.] 
Sources  and  Modes  of  Infection,  by  Charles  V.  Chapin,  M.U.,  Sc.D. 

[John  Wiley  and  Sons.] 


TABLE   OF  CONTENTS 

PAGE 

TEACHERS'  PREFACE vii 


CHAPTER  I 
INTRODUCTION .1 

CHAPTER  II 

STRUCTURE,  MODE  OF  DEVELOPMENT,  AND  COMPOSITION 

OF  BACTERIA 7 

CHAPTER  III 
METHODS  OF  STUDY 15 

CHAPTER  IV 

THE  EFFECT  OF  PHYSICAL  AND  CHEMICAL  AGENTS  UPON 

BACTERIA,  AND  THE  EFFECTS  OF  BACTERIAL  GROWTH      27 

CHAPTER  V 
THE  RELATIONS  OF  BACTERIA  TO  DISEASE         ...      46 

CHAPTER  VI 
IMMUNITY 64 

CHAPTER  VTI 

INFLAMMATION,     SUPPURATION,     PNEUMONIA,      EPIDEMIC 

CEREBRO-SPJNAI.  MENINGITIS 66 

xi 


Xii  TABLE   OF   CONTENTS 

CHAPTER   VIII 

PAGE 

THE  VENEREAL  DISEASES:  GONORRHEA,  SYPHILIS    .        .      76 

CHAPTER  IX 
TUBERCULOSIS.    LEPROSY 85 

CHAPTER  X 
GLANDERS,  ACTINOMYCOSIS,  ANTHRAX         ....    100 

CHAPTER  XI 
TYPHOID  FEVER  (ENTERIC  FEVER) 108 

CHAPTER  XH 
DIPHTHERIA 117 

CHAPTER  XIII 
TETANUS,  INFLUENZA,  BUBONIC  PLAGUE     .        .        .        .    126 

CHAPTER  XIV 
ASIATIC  CHOLERA,  RELAPSING  FEVER 147 

CHAPTER  XV 
AM<EBIC  DYSENTERY,  MALARIAL  FEVER      ....     155 

CHAPTER  XVI 

INFECTIOUS  DISEASES  OF  UNKNOWN  CAUSE:  SMALLPOX 
(VARIOLA),  HYDROPHOBIA  (RABIES),  SCARLET  FEVER, 
MEASLES,  WHOOPING  COUGH,  MUMPS,  YELLOW  FEVER  162 

CHAPTER  XVII 
BACTERIA  IK  AIR,  SOIL,  WATER,  AND  FOOD       .        .        .     172 

INDEX  .    177 


BACTERIOLOGY  FOR  NURSES 


BACTEBIOLOGY   FOR  NUKSES 
CHAPTER  I 

INTRODUCTION 

The  Discovery  of  Bacteria.  —  Bacteria  are  the 
smallest  and  simplest  known  form  of  plant  life, 
although  no  other  class  of  plants  compares  with 
them  in  importance.  The  study  of  bacteria  began 
with  the  development  of  the  microscope.  While 
several  writers  of  antiquity  surmised  that  such 
microorganisms  existed,  and  advanced  some  really 
marvelous  speculations  as  to  their  place  in  nature, 
yet  it  was  not  until  a  Dutch  lens-maker,  Leeuwen- 
hoek  (1632-1723),  perfected  a  lens  of  higher  power 
than  had  been  made  before,  that  bacteria,  or  "  ani- 
malcules," as  he  designated  them,  were  seen  and 
described.  In  1675  Leeuwenhoek  published  the 
fact  that  he  had  perfected  a  lens  whereby  he  could 
detect  in  a  drop  of  rainwater,  living,  moving  "ani- 
malcules" smaller  than  anything  which  had  hitherto 
been  seen.  He  found  them  in  sea-water,  in  well- 
water,  in  feces,  and  in  the  tartar  scraped  from  his 

B  1 


2  BACTERIOLOGY   FOR   NURSES 

teeth,  and  also  discovered  that  they  differed  in  size, 
shape,  and  motility;  his  descriptions  and  plates 
leave  no  doubt  but  what  we  now;  know  as  bacteria 
were  the  "animalcules"  which  he  first  saw  with  his 
simple  lens. 

Leeuwenhoek  made  no  attempt  to  formulate  a 
theory  as  to  the  place  these  microorganisms  occu- 
pied in  nature,  but  his  discovery  of  their  presence 
in  water  and  in  the  intestinal  evacuations  led  to  the 
first  association  of  bacteria  and  disease  in  the  minds 
of  medical  scientists.  Nothing  was  done  at  this 
time,  however,  in  the  way  of  classifying  or  separat- 
ing the  organisms,  although  men  did  not  hesitate  to 
declare  them  to  be  the  cause  of  diseases  of  various 
kinds. 

In  1762,  nearly  a  century  later,  Plenciz,  a  Vienna 
physician,  confirmed  Leeuwenhoek's  discoveries, 
and  declared  that  to  these  " animalcules"  was  due 
all  of  the  infectious  diseases;  that  the  material  of 
infection  must  be  a  living  substance,  and  endeav- 
ored to  explain  upon  this  ground  the  period  of  incu- 
bation. Plenciz  believed  that  each  disease  was  due 
to  a  special  germ,  which  was  capable  of  multiplica- 
tion within  the  human  body  and  could  be  trans- 
mitted to  others.  That  these  doctrines  of  Plenciz 
should  have  been  lost  sight  of  seems  almost  incred- 


INTRODUCTION  3 

ible  at  this  time,  but  they  were  regarded  by  many 
as  evidences  of  an  unbalanced  mind,  most  writers  at 
that  period  doubting  the  possibility  of  the  micro- 
organisms being  living  things.  In  1786  a  Danish 
zoologist,  Muller,  described  many  structural  details 
of  bacteria  of  which  his  predecessors  were  ignorant, 
and  also  recognized  the  extreme  difficulties  of  study- 
ing such  minute  organisms.  "The  difficulties,"  he 
writes,  "that  beset  the  investigators  of  these  micro- 
scopic animals  are  countless;  the  sure  and  definite 
determination  [of  species]  requires  so  much  time, 
so  much  acumen  of  eye  and  judgment,  so  much 
perseverance  and  practice,  that  there  is  hardly 
anything  so  difficult."  (Jordan.) 

In  1838  Ehrenberg  (1795-1876)  made  a  valuable 
contribution  to  the  subject  in  his  work  on  "Infu- 
soria," as  the  organisms  found  in  infusions  of  meat, 
hay,  and  other  substances  were  .called.  Ehrenberg 
was  the  first  to  introduce  a  really  systematic 
method  for  the  study  of  bacteria. 

It  was  not  until  Louis  Pasteur  (1822-1895),  about 
1850,  began  his  investigations  upon  the  souring  and 
putrefaction  of  beer  and  wine  that  bacteria  were 
recognized  as  organisms  whose  activities  were  of 
such  significance  to  the  human  race. 

For  two  hundred  years  prior  to  Pasteur's  investi- 


4  BACTERIOLOGY    FOR    NURSES 

gations,  scientists  had  been  discussing  whether 
Leeuwenhoek's  "  animalcules  "  generated  spontane- 
ously as  the  result  of  putrefaction  or  not,  even  so 
great  a  chemist  as  Liebig  held  to  the  theory  of 
spontaneous  generation. 

Pasteur  proved  the  utter  fallacy  of  spontaneous 
generation,  and  further  showed  that  putrefaction 
was  a  chemical  change,  produced  by  the  activities 
of  the  bacteria  in  their  search  for  food.  It  was 
Pasteur  who  discovered  that  the  souring  of  milk 
was  due  to  bacteria,  and  that  certain  bacteria  are 
the  cause  of  certain  diseases. 

Pasteur  did  not  first  discover  these  microor- 
ganisms, nor  study  them  first,  nor  first  suggest 
their  connection  with  disease,  but  he  proved  these 
theories  by  rigid  experiments;  proved  these  and 
many  other  theories  beyond  question,  which  gave 
him  the  title  of  founder  of  bacteriology. 

The  profound  importance  of  Pasteur's  work  to  the 
world  is  universally  recognized.  In  1892  Lord  Lister 
said:  "  Truly  there  does  not  exist  in  the  entire 
world  any  individual  to  whom  the  medical  sciences 
owe  more  than  they  do  to  Pasteur.  .  .  .  Thanks  to 
him,  surgery  has  undergone  a  complete  revolution, 
which  has  deprived  it  of  its  terrors  and  has  extended 
almost  without  limit  its  efficacious  powers." 


INTRODUCTION  5 

In  1876  Robert  Koch  first  demonstrated  that 
anthrax  in  cattle  was  due  to  the  Bacillus  anthracis. 

Until  1882  the  methods  of  study  and  observation 
of  bacteria  were  so  imperfect  that  it  was  almost 
impossible  to  isolate  a  single  species,  and  the  process 
was  attended  with  so  much  uncertainty  that  inves- 
tigators were  often  not  sure  whether  they  were 
dealing  with  one  or  more  species. 

At  this  time  Koch  invented  the  solid  culture 
media,  whereby  it  became  possible  to  easily  isolate 
a  single  species,  Weigert  suggested  the  use  of  ani- 
line dyes  as  a  means  of  differentiation,  and  the 
use  of  animals  as  a  means  of  obtaining  pure  cul- 
tures began. 

From  Koch's  series  of  brilliant  investigations, 
bacteriology  is  said  to  have  been  placed  within  the 
reach  of  men  who  were  not  geniuses  like  Pasteur 
and  himself,  and  may  be  justly  said  to  have  had 
its  birth. 

The  development  of  bacteriology  in  the  last 
twenty-five  years  has  been  marvelously  rapid, 
causing  an  almost  complete  revolution  in  the  whole 
practice  of  medicine,  and  opening  methods  of 
agriculture  and  other  industries  which  have  proved 
of  infinite  benefit  to  the  whole  world.  The  fact 
that  until  Pasteur's  researches  in  the  middle  of 


6  BACTERIOLOGY    FOR   NURSES 

the  nineteenth  century  the  familiar  processes  of 
putrefaction  and  fermentation  were  not  understood, 
and  that  the  causes  of  infectious  diseases  were 
equally  obscure,  shows  what  an  important  change 
took  place  in  man's  conception  of  the  living  world 
around  him,  when  Pasteur  and  Koch  founded 
bacteriology. 

The  part  played  by  bacteria  in  the  causation  of 
disease  may  be  regarded  as  of  surpassing  importance, 
but  the  work  done  by  them  in  other  directions 
exerts  a  mighty  influence  upon  the  welfare  of  man- 
kind. Bacteria  not  only  act  as  scavengers  in  de- 
stroying dead  organic  material,  but  they  also  change 
the  form  of  important  chemical  elements,  such  as 
nitrogen  and  carbon,  into  substances  which  are 
available  for  the  nutrition  of  the  higher  plants, 
thus  proving  themselves  as  important  in  construc- 
tive as  in  destructive  processes. 


CHAPTER  II 

STRUCTURE,    MODE    OF    DEVELOPMENT,    AND    COMPO- 
SITION  OF   BACTERIA 

MORPHOLOGY  is  the  science  which  deals  with 
the  form  and  structure  of  organisms. 

Bacteria  are  the  smallest  and  simplest  known 
form  of  vegetable  organisms.  They  are  unicellu- 
lar (having  but  one  cell)  and  multiply  by  fission 
(splitting  into  equal  parts). 

The  individual  cells  differ  in  size,  shape,  and 
structure,  which  can  be  determined  only  by  the 
use  of  the  microscope;  but  in  masses  of  cells  or 
"  colonies,"  as  they  are  called,  which  develop 
in  suitable  substances,  they  often  present  differ- 
ences in  form,  color,  and  consistency  which  may 
be  detected  with  the  naked  eye. 

Size.  —  Different  bacteria  vary  greatly  in  size, 
the  average  of  the  rod-shaped  bacterium  being 
about  0.5/u,  in  diameter  (1/ot  =  1  micron  or  micro- 
millimeter  =  YflVo  mm.  =  about  ^TFOTF  inch).  The 
bacillus  of  typhoid  fever  ranges  from  I/A  to  3/x, 


8  BACTERIOLOGY   FOR   NURSES 


mch)  m  length;  the  largest  (pathogenic) 
bacterium  known  is  the  spirillum  (screw-shaped)  of 
relapsing  fever  ;  the  bacillus  of  influenza  is  one  of  the 
smallest  of  the  pathogenic  forms,  although  there  are 
known  to  be  smaller  organisms  which  are  too  minute 
to  be  seen  with  the  present  microscopes  ;  the  virus 
of  yellow  fever  will  pass  through  a  porcelain  filter  ; 
the  germs  of  pleuro-pneumonia  and  foot-and-mouth 
disease  in  cattle  are  too  small  to  be  observed  (ultra- 
microscopic). 

Shape.  —  The  forms  of  bacteria  are  exceedingly 
simple,  comprising  three  types  —  the  rod,  the  sphere, 


\ 
a  b  c 

a.  Single  bacilli.        6.  Bacilli  in  pairs.       c.  Bacilli  in  threads. 


a  b  c  d  e 

a.  Staphylococci.    6.  Streptococci,    c.  Diplococci.   d.  Tetrads,    e.  Sarcinae 


2 


a  be 

a.  and  c.  Spirilla  in  comma  forms  and  longer  threads  known  as  spiro- 

chaeta.    6.  Thick  spirals  sometimes  known  as  vibrios. 

FIG.  1. 


DEVELOPMENT    AND    COMPOSITION    OF    BACTERIA        9 

and  the  spiral.  The  rods  are  known  as  bacilli 
(sing,  bacillus),  the  spheres  as  cocci  (sing,  coccus), 
and  the  spirals  as  spirilla  (sing,  spirillum).  More 
baccilli  are  known  than  any  other  form,  and  cocci 
are  much  more  numerous  than  spirilla. 

Long-continued  growth  in  artificial  media  some- 
times causes  abnormal  forms  of  growth,  just  as 
unnatural  surroundings  and  conditions  produce 
deformities  in  the  higher  forms  of  life. 

Structure. — The  internal  structure  of  bacteria 
is  exceedingly  simple :  there  appears  to  be  a  mem- 
branous covering,  including  the  protoplasm  (ger- 
minal matter),  which  is  not  always  clearly  discern- 
ible, but  in  some  species  (micrococcus  of  pneumonia) 
may  be  seen  as  a  sharply  defined  capsule  inclosing 
a  clear  zone. 

The  nature  of  the  cell-substance  is  still  imper- 
fectly understood;  the  question  of  the  existence 
of  a  nucleus  and  the  significance  of  the  internal 
structure  are  still  disputed  points  which  present  one 
of  the  exceeding  difficulties  of  which  Muller  wrote 
in  1786. 

Motility.  —  The  power  of  motion  in  certain  species 
of  bacteria  is  due  to  hair-like  appendages,  or  flagella, 
which  by  a  lashing  movement  enable  them  to  move 
through  fluids.  The  flagella  vary  in  their  position 


10  BACTERIOLOGY   FOR   NURSES 

upon  the  cell-body,  sometimes  occurring  at  one 
end,  sometimes  at  both  ends,  and  in  others  entirely 
surrounding  the  bacterium,  as  in  the  bacillus  of 
typhoid  fever. 


a  b                              c 

FIG.  2.  —  a.  Spiral  forms  with  flagellum  at  one  end.    6.  Spirals  from 

water  with  flagella  at  both  ends.  c.  Bacilli  of  typhoid  fever  with  flagella 
on  all  sides. 

The  majority  of  bacteria  having  motility  are 
bacilli  or  spirilla. 

Mode  of  Multiplication.  —  When  bacteria  have 
reached  their  maximum  size,  cell-division  occurs, 
which  divides  the  cells  into  two  equal  parts.  Bacilli 
and  spirilla  divide  by  transverse  fission;  while 
among  the  cocci  division  may  occur  in  one  plane, 
which  results  in  chains  (streptococci),  or  in  two 
planes,  resulting  in  groups  (staphylococci),  or  m 
three  planes,  resulting  in  packets  (sarcinse). 

Under  favorable  conditions  fission  occurs  rapidly 
(the  hay  bacillus  in  thirty  minutes),  from  which 
may  be  readily  estimated  the  enormous  multi- 
plication which  would  result,  should  nothing  occur 
to  check  the  reproduction.  In  a  single  twenty-four 
hours  the  increase  would  reach  hundreds  of  millions, 


DEVELOPMENT   AND    COMPOSITION    OF    BACTERIA      11 

but,  as  is  the  case  with  all  organisms,  mathematical 
increase  never  continues  without  check  or  hindrance. 

In  the  case  of  bacteria  the  check  arises  largely  from 
the  products  of  the  bacteria  themselves;  the  organ- 
isms in  their  activity  upon  food  substances  produce 
acids  and  other  injurious  materials  which  check 
further  multiplication.  Lack  of  proper  food,  or 
moisture,  or  favorable  temperature,  and  conflict 
with  other  species  of  organisms,  are  also  checks 
upon  growth  and  multiplication. 

Spore-formation.  —  Following  a  period  favorable 
to  reproduction,  certain  bacteria  (notably  bacilli) 
enter  into  a  stage  known  as  spore-formation;  this 
usually  occurs  when  food  nears  exhaustion,  or 
injurious  substances  have  been  formed,  or  unfavor- 
able temperature  conditions  arise,  and  is  character- 
ized by  the  development  of  round  or  oval  glisten- 
ing bodies  (spores)  within  the  cell  which  are  of 
dense  compact  structure  and  possess  an  extraor- 
dinary resistance  to  heat  (70°-100°  C.,  or  158°- 
212°  F.),  chemicals,  and  other  injurious  sub- 
stances. 

A  single  cell  produces  but  one  spore,  as  a  rule, 
although  there  are  said  to  be  rare  exceptions. 

Spore-forming  bacteria  are  said  to  be  in  the 
vegetative  stage  while  growth  and  reproduction 


12  BACTERIOLOGY   FOR  NURSES 

are  taking  place.  The  spore-stage  is  considered  a 
resting  state  in  which  the  organisms  are  able  to 
resist  harmful  influences  to  a  much  greater  degree 
than  when  in  the  vegetative  state.  As  soon  as  fav- 


f  « 

«  c  \ 


FIG.  3.  —  Showing  spore-formation. 

orable  conditions  of  moisture,  temperature,  and 
food  return,  the  spores  develop  again  into  the  same 
kind  of  cells  from  which  they  originated. 

Spore-formation  is  not  common,  occurring  most 
frequently  in  bacilli,  less  so  in  spirilla,  and  rarely 
in  micrococci;  however,  it  is  supposed  that  spore- 
formation  may  take  place  in  species  growing  under 
natural  conditions,  but  which  are  impossible  to 
cultivate  under  artificial  surroundings. 

The  vitality  of  the  spore  may  remain  dormant 
for  months  or  years,  perhaps  indefinitely,  a  fact 
which  is  of  peculiar  significance  in  the  consideration 
of  certain  infectious  diseases. 

Masses  of  Cells  or  Colonies.  —  By  implanting 
upon  suitable  medium  one  or  more  cells  of  a  species 
of  bacteria,  and  subjecting  the  culture  to  favorable 
conditions  of  moisture  and  temperature  for  a  few 


DEVELOPMENT   AND   COMPOSITION    OF   BACTERIA      1 

hours  or  days,  a  mass  of  cells,  or  colony,  will  often 
be  seen  with  the  naked  eye.  In  different  species 
these  colonies  are  often  strongly  characteristic, 
varying  with  the  culture  media  and  the  conditions 
under  which  they  are  grown. 

Besides  shape,  size,  and  general  appearance, 
color  is  often  a  characteristic  difference;  but  while 
these  differences  are  important,  bacteriologists  do 
not  rely  upon  observations  made  with  the  naked 
eye  (macroscopic). 

"The  attempt  to  determine  species  of  bacteria 
by  ordinary  macroscopic  methods  leads  to  difficul- 
ties of  the  same  kind  as  would  be  met  if  we  tried 
to  differentiate  species  from  the  marks  presented 
by  masses  of  trees  in  forests  from  a  distance  — 
say,  in  a  balloon.  A  forest  of  a  given  species  of 
tree  would  appear  different  at  different  seasons,  and 
according  to  its  age,  the  kind  of  soil,  climate,  and 
so  on,  and  the  treatment  it  had  received  previous 
to  planting."  (Marshall  Ward.) 

The  Chemical  Composition  of  Bacteria.  —  The 
bodies  of  bacteria  are  made  up  of  about  80  per 
cent  of  water,  the  amount  varying  with  the  species 
and  the  nature  of  the  culture  medium;  the  usual 
analysis  being: 


14  BACTERIOLOGY   FOR   NURSES 

Water 85.45% 

Proteins 10.33% 

Fatty  substances 7  % 

Ash 1.75% 

Residue 1.57+% 

Sulphur,  potassium,  calcium,  magnesium,  phos- 
phoric acid,  iron,  and  silica  are  found  in  varying 
amounts. 

Cellulose,  the  predominant  element  in  the  higher 
forms  of  plants,  is  absent  from  bacteria,  and  the 
nature  of  the  protein  substances  of  bacteria  are 
little  understood. 


CHAPTER  III 

METHODS  OF  STUDY1 

THE  slow  development  of  bacteriology  was  largely 
due  to  the  lack  of  method  in  the  study;  and  not 
until  Pasteur,  Koch,  and  others  demonstrated 
that  methods  of  scientific  exactness  must  be  em- 
ployed was  any  real  progress  made.  Until  this 
was  done  the  mere  fact  that  bacteria  existed  stood 
for  very  little,  as  no  one  could  say  what  effects 
they  produced  nor  what  part  they  filled  in  the 
scheme  of  nature. 

"The  technique  of  bacteriology  is  one  of  its 
greatest  contributions  to  both  science  and  art,  and 
the  use  of  so  valuable  and  simple  a  tool  should  be 
mastered  not  only  by  the  biological  teacher,  but 
by  practical  workers  in  medicine,  hygiene,  and 
many  other  fields."  (Jordan.) 

While  bacteriological  work  in  the  laboratory 
will  be  no  part  of  a  graduate  nurse's  duty,  a  short 
course  when  she  is  a  pupil  is  necessary  to  prepare 

1  For  reference :  A  Laboratory  Guide  in  Bacteriology,  Heinemann. 
15 


16  BACTERIOLOGY   FOR  NURSES 

her  for  the  various  departments  of  nursing;  for 
she  cannot  protect  herself  nor  others  from  con- 
tagious matter,  if  she  does  not  thoroughly  under- 
stand the  sources  of  infection,  the  methods  of 
transmission,  and  the  means  employed  to  prevent 
it.  Without  a  working  knowledge  of  the  technique 
of  bacteriology  she  can  neither  grasp  nor  practice 
aseptic  surgical  technique,  which  in  its  elaborate 
detail  appears  nothing  short  of  an  absurdity  to  the 
ignorant,  but  to  a  nurse  well  trained  in  first  prin- 
ciples and  daily  routine,  becomes  an  instinct  as 
much  a  part  of  her  life  as  the  instinctive  avoidance 
of  fire  or  any  other  dangerous  element. 

The  schedule  of  exercises  in  the  laboratory  out- 
lined in  this  little  book  should  prepare  the  pupil- 
nurse  not  only  for  her  duties  in  operating  and 
dressing  rooms,  contagious  and  maternity  wards, 
but  for  a  better  understanding  of  every  nursing 
requirement  from  dusting  the  ward  upward.  She 
must  know  why  sputum  cups  and  bedpans  need 
disinfection  as  well  as  scrubbing,  why  certain 
dishes  are  separated  from  others  and  sterilized, 
why  catheters  and  douche  points  require  such 
minute  care,  why  in  certain  cases  the  excreta  as 
well  as  the  bed  linen  must  be  disinfected,  etc. 
It  is  not  enough  to  give  a  nurse  the  merely  mechani- 


METHODS    OF   STUDY  17 

cal  part  of  her  training  without  teaching  her  the 
principles  which  should  guide  the  performance  of 
her  duties,  for  without  this  knowledge  she  holds  in 
her  hands  a  capacity  for  doing  infinite  harm;  she 
cannot  avoid  dangers  which  she  does  not  recognize. 

To  the  medical  student  the  study  of  bacteriology 
has  an  entirely  different  meaning;  his  application 
of  the  knowledge  gained  is  for  other  purposes,  viz. 
as  a  means  of  diagnosis  and  treatment,  —  two  ob- 
jects which  do  not  in  any  way  concern  the  nurse, 
whose  sole  interest  is  for  the  purpose  of  enabling 
her  to  intelligently  execute  her  nursing  and  house- 
keeping technique,  the  two  departments  being 
too  closely  related  to  be  separated. 

In  the  recent  development  of  bacteriology  as 
related  to  disease,  a  tendency  has  been  observed  to 
work  along  two  lines,  pathologic  and  hygienic ;  the 
first,  considering  chiefly  the  effects  produced  upon  the 
body  by  the  presence  of  bacteria  and  their  toxins,  and 
the  defenses  of  the  body ;  while  in  hygienic  bacte- 
riology especial  attention  is  given  to  the  channels  by 
which  bacteria  leave  the  body  and  how  they  may 
again  infect  healthy  persons. 

Where  Bacteria  are  Found.  —  Before  beginning  the 
study  of  bacteria  it  is  necessary  to  have  firmly  fixed 
in  the  mind  the  fact  that  bacteria  are  found  every- 


18  BACTERIOLOGY   FOR   NURSES 

where;  wherever  air  and  dust  find  their  way  bacteria 
are  present.  In  the  minutest  crevices,  too  small  to 
be  seen  with  the  naked  eye,  like  those  in  the  skin, 
upon  the  hair,  upon  all  fabrics,  furniture,  walls, 
floors,  plants;  in  the  earth,  water,  and  food  they  may 
be  found  ;  in  fact,  we  may  truthfully  say  they  are 
everywhere. 

The  first  and  probably  the  greatest  difficulty  which 
beset  the  early  investigators  was  the  presence  of  num- 
berless kinds  together,  which  effectually  prevented 
any  opportunity  to  isolate  a  single  species  for  obser- 
vation. It  was  early  discovered  that  bacteria  would 
grow  in  groups  (colonies)  which  were  sometimes 
visible  to  the  naked  eye,  but  the  microscope  would 
reveal  not  one  species  which  might  be  studied,  but 
a  dozen  or  more,  and  thus  for  years  scientists  labored 
to  devise  some  method  whereby  they  might  isolate 
a  single  kind  and  study  its  habits. 

Bacteria  were  first  grown  artificially  in  bouillon 
(beef  broth),  which  was  called  the  culture  medium, 
but  the  multiplicity  of  species  and  the  fluid  medium 
were  serious  obstacles  which  blocked  the  way  of  sys- 
tematic observation,  and  not  until  Robert  Koch 
found  that  gelatin  was  not  unfavorable  to  bacterial 
growth,  and  would  solidify  the  broth,  besides  being 
transparent,  was  it  possible  for  pure  cultures  to  be 


METHODS   OF   STUDY 


19 


obtained.  Meanwhile,  investigators  found  that  to 
secure  pure  cultures,  all  utensils,  media,  or  anything 
coming  in  contact  with  them  must  be  freed  of  bacte- 
ria ;  i.e.  the  bacteria  must  be  destroyed,  or,  as  we 
now  say,  these  articles  must  be  "  sterilized, "  or  the 
cultures  would  not  be  pure,  but  a  mixture  of  many 
species. 

It  was  found  that  cotton  used  as  a  cork  for  flasks 
and  culture  tubes  would  allow  the  passage  of  air 
which  was  nec- 
essary for  the 
growth  of  the 
aerobic  bacteria, 
but  would  ex- 
clude the  en- 
trance of  bacteria 
in  the  air. 

Later   Weigert  FIG.  4. -Culture  tube.       Tubes  of  media. 

Suggested  the USe     a.  Ordinary  upright  tube.    b.  Sloped  tube.    o.  "Deep" 
tube  for  cultures  of  anaerobes. 

of    aniline   dyes 

for  staining  bacteria,  which  were  found  to  take  the 
dyes  each  in  its  characteristic  way,  thus  enabling 
the  observer  to  identify  certain  species,  and  from 
these  simple  beginnings  the  elaborate  minutiae  of 
the  technique  of  bacteriology  has  grown  —  practi- 
cally all  within  thirty-five  years. 


20 


BACTERIOLOGY   FOR   NURSES 


Sterilization.  —  Properly,  sterilization  means  the 
complete  destruction  of  bacteria,  by  whatever  means; 
but  by  custom  in  the  laboratory  sterilization  is  used 
when  heat  is  the  agent  employed,  and  disinfection  is 
used  to  designate  sterilization  by  chemicals. 

Sterilization  by  heat  may  be  accomplished  by  dry 
heat,  as  by  baking  or  passing  an  object  through  a 
flame,  or  by  moist  heat,  such 
as  boiling,  or  by  steam,  with  or 
without  pressure.  Sterilization 
by  heat  is  commonly  employed 
for  the  sterilization  of  utensils, 
instruments,  and  culture  media, 
as  the  action  of  chemicals 
would  be  unfavorable  to  the 
cultivation  of  bacteria;  but 
chemicals  are  used  for  disin- 
fecting the  hands,  old  cultures, 
and  all  useless  infective  materials. 

It  is  estimated  that  bacteria  and  spores  exposed  to 
a  temperature  of  170°  C.  (338°  F.)  for  one  hour  will 
be  completely  destroyed. 

There  are  a  number  of  hot-air  sterilizers  in  com- 
mon use  which  give  a  uniform  heat  in  all  parts  of 
the  oven. 
Sterilization  by  steam  under  pressure  is  accom- 


FIG.  5.  —  Laboratory  hot- 
air  sterilizer. 


METHODS    OF   STUDY 


21 


0  0    O    O    O 


plished  by  means  of  an  autoclave,  which  is  a  strong 
iron  cylinder  standing  upright,  closed  at  the 
bottom  and  furnished  with  a  tight-  6 

fitting  lid,  and  provided  with  a  ther- 
mometer, a  steam  valve,  a  safety 
valve,  and  a  gauge  whereby  the  tem- 
perature and  pressure  may  be  regu- 
lated, heat  being  furnished  by  Bunsen 
gas  burners  or  by  indirect  steam  from 
a  central  boiler.  For  culture  media 
in  tubes  an  exposure  of  five  minutes 
at  120°  C.  (248°  F.)  is  sufficient  to 
destroy  all  bacteria,  but  for  media  in 


bulk  an  exposure  of  fifteen  minutes  FIG.  6.  —  Autoclave. 

is  necessary. 

Certain  culture  media  are  injured 

by  exposure  to  great  heat 
under  pressure,  and  this  fact, 
together  with  the  extraordi- 
nary resistance  of  the  spores 
of  certain  species  of  bacteria, 
led  to  the  employment  of  frac- 
tional or  discontinuous  sterili- 
zation. The  ordinary  Arnold 
steam  sterilizer  used  in  the 
FIG. 7. -Bunsen burner,  kitchen  for  the  sterilization  of 


a.  Safety-valve. 

b.  Blow-off  pipe. 

c.  Gauge. 


22 


BACTERIOLOGY   FOR   NURSES 


milk  is  usually  employed,  the  culture  tubes  being 
exposed  to  100°  C.  (212°  F.)  for  fifteen  minutes  on 
three  successive  days  and  in 
the  intervals  kept  at  ordinary 
room  temperature;  in  this 
way  spores  which  develop 
after  the  first  sterilization 
may  be  destroyed  after  the 
second  or  third. 

Filtration  of  fluids  through 
filter  paper  or  absorbent  cotton 
is  employed  as  an  important 
adjunct  of  sterilization. 

Instruments,  such  as  for- 
ceps, scissors,  knives,  metal  syringes,  and  hypoder- 
mic needles,  are  usually  sterilized  by  boiling  in  a 
2  per  cent  soda  solution  for  ten  minutes,  before  and 
after  using,  the  addition  of  soda  preventing  rust. 
Platinum  wires 

used  for  trans-  f 1 

ferring  bacteria 
are      sterilized 

FIG.  9.  — Platinum  wires. 

by      passing 

slowly  through  a  gas  flame  until  red  hot  and  allowing 
them  to  cool  before  using.  These  wires  must  be 
sterilized  both  before  and  after  using,  never  being  laid 


Fia.  8.— Arnold  steam 
sterilizer. 


METHODS   OF   STUDY  23 

upon  the  table  before  sterilizing,  as  the  purpose  for 
which  they  are  used  makes  them  a  constant  source 
of  danger. 

Cleaning  Glassware.  —  The  glassware  used  in  the 
laboratory  consists  of  flasks,  culture  tubes,  and 
dishes  of  various  sizes  and  shapes,  with  and  with- 


Petri  dish.  FIG.  10.  Stender  dish. 

(Cover  shown  partially  raised.) 

out  covers,  small  oblong  (1x2  inches)  pieces  of 
glass  called  slides,  small  round  cover  glasses,  glass 
rods,  and  glass  pencils. 

When  new  or  after  using,  glassware  should  be  put 
into  a  strong  soapsuds,  which  should  be  brought  to 
the  boiling  point 

and  continued  for    ^       <^===ss^^is== 
ten    minutes,    fol-    ^        ^J         <g\ 


lowed  by  vigorous        FlG  u._Novy,s cover.giass  forceps, 
brushing    with    a 

tube-brush,  rinsed  with  running  water  until  every 
particle  of  soap  has  been  removed,  turned  upside 
down  to  drain  in  a  wire  basket,  and  put  into  the 
hot-air  sterilizer  for  twenty  minutes. 


24  BACTERIOLOGY  FOR  NURSES 

If  the  soapsuds  is  not  effective  and  the  glass  has 
become  cloudy  with  use,  a  cleaning  mixture  may  be 
used  which  contains  — 

Potassium  dichromate 60  parts 

Water 300  parts 

Concentrated  sulphuric  acid      ....    460  parts 

the  sulphuric  acid  being  added  slowly  with  con- 
stant stirring.  Especial  care  must  be  given  to  re- 
move all  traces  of  the  acid  by  generous  rinsing. 

Plugging  Culture  Tubes  and  Flasks. — The  plugging 
of  culture  tubes  and  flasks  is  done  by  inserting  a  suit- 
able quantity  of  good  cotton  into  the  neck  of  the  tube 
or  flask  about  three  quarters  of  an  inch  with  a  glass 
rod.  The  plug  should  be  rolled  smoothly,  but  not  so 
tightly  as  to  entirely  exclude  the  passage  of  air.  If  not 
rolled  smoothly,  bacteria  will  gain  access  to  the  tube  in 
the  crevices  between  the  plug  and  the  glass.  Neither 
should  the  plug  be  so  loose  that  parts  of  the  cotton 
will  separate  when  the  plug  is  removed,  nor  so  large 
that  the  entrance  end  rubs  the  outer  rim  of  the  tube 
when  it  is  inserted.  These  details  may  seem  exceed- 
ingly trivial,  but  the  observance  of  these  minutiae  is 
what  distinguishes  good  technique  from  haphazard 
methods  which  fail  utterly  to  accomplish  the  desired 
results.  The  plugged  culture  tubes  are  then  placed 


METHODS    OF    STUDY  25 

in  the  hot-air  sterilizer  at  150°  C.  (302°  F.)  for  sixty 
minutes,  when  the  cotton  plugs  will  be  charred  to  a 
light  brown  color  and  will  retain  their  shape. 

Culture  Media.  —  Certain  food  substances  are  nec- 
essary for  the  cultivation  of  bacteria,  which  are 
known  as  culture  media,  and  by  the  behavior  of  dif- 
ferent species  upon  the  various  media  it  is  possible  for 
the  observer  to  recognize  their  kind. 

The  most  common  media  are  bouillon,  gelatin, 
agar,  potato,  and  blood-serum,  besides  a  multitude 
of  special  media  for  more  advanced  work. 

Formulae  for  making  culture  media  are  a  part  of 
the  equipment  of  every  laboratory,  and  must  be  so 
closely  followed  that  no  attempt  will  be  made  to 
embody  them  here. 

The  making  of  culture  media  is  excellent  practice, 
as  the  most  accurate  measurements  and  management 
are  required ;  otherewise  failure  is  a  sure  result. 

Staining.  —  As  before  mentioned,  the  staining  of 
bacteria  is  an  important  method  of  distinguishing  a 
species,  as  various  kinds  stain  in  a  fixed  and  char- 
acteristic manner.  The  aniline  dyes  used  most 
commonly  are  gentian-violet,  methylene-blue,  and 
fuchsin  (reddish  pink). 

A  sterilized  slide  has  placed  upon  it  a  drop  of 
water  to  which  is  added  a  small  amount  of  bacterial 


26  BACTERIOLOGY   FOR  NURSES 

growth,  the  two  being  mixed  and  spread  evenly 
upon  the  glass.  This  film  is  allowed  to  dry  in 
the  air  and  is  then  passed  through  the  flame  of 
a  spirit  lamp  or  Bunsen  burner  three  or  four  times 
to  fix  the  film,  which  is  then  covered  with  the  stain 
and  allowed  to  stand  twenty  or  thirty  seconds,  fol- 
lowed by  washing  in  clear  water,  when  it  may  be 
observed  with  a  microscope,  and  different  kinds  of 
bacteria  are  often  easily  recognized  even  by  very 
inexperienced  observers.  This  is  a  bare  outline  of 
how  bacteria  are  stained,  the  method  being  greatly 
elaborated  for  different  species  and  conditions. 

The  microscope  is  an  indispensable  adjunct  to 
work  in  the  laboratory,  the  use  of  which  requires 
practice  and  delicate  care. 

Animal  Inoculation.  —  Animal  inoculations  are 
employed  to  observe  the  virulence  of  bacteria,  to 
secure  pure  cultures,  and  for  continuing  the  life  of 
such  organisms  as  cannot  be  grown  outside  of  the 
animal  body,  such  as  the  virus  of  smallpox  and 
hydrophobia. 

Rabbits,  guinea  pigs,  white  rats,  and  white  mice 
are  most  commonly  used. 


CHAPTER  IV 

THE  EFFECT  OF  PHYSICAL  AND  CHEMICAL  AGENTS 
UPON  BACTERIA,  AND  THE  EFFECTS  OF  BACTE- 
RIAL GROWTH 

LIKE  the  higher  forms  of  vegetation,  bacteria  are 
susceptible  to  many  influences,  the  physical  and 
chemical  conditions  which  surround  them  deter- 
mining whether  they  shall  live  and  multiply,  or 
lie  dormant,  or  perish. 

Temperature.  —  Three  points  of  temperature  are 
considered  in  the  growth  of  different  bacteria:  a 
minimum  being  the  lowest  point  at  which  growth 
occurs,  an  optimum  being  the  temperature  of  most 
luxuriant  growth,  and  the  maximum  being  the  high- 
est degree  at  which  growth  can  take  place. 

The  extremes  of  temperature  between  which  the 
majority  of  bacteria  are  known  to  grow  are  5.5°  C. 
(41.9°  F.)  and  43°  C.  (109.4°  F.),  although  species 
exist  which  may  multiply  at  70°  C.  (158°  F.)  and 
others  as  low  as  0°  C.  (32°  F.). 

The  bacteria  commonly  found  in  soil  and  water 

27 


28  BACTERIOLOGY   FOR   NURSES 

and  the  bacilli  of  diphtheria  and  typhoid  fever  are 
much  less  sensitive  to  low  degrees  of  temperature 
than  to  extremes  of  heat,  sometimes  surviving 
weeks  of  freezing.  A  certain  species  of  bacteria 
commonly  found  in  sewage  shows  no  signs  of  growth 
in  a  temperature  below  60°  C.  (140°  F.).  The 
favorable  degree  of  temperature  for  the  develop- 
ment of  most  pathogenic  bacteria  is  that  of  the  hu- 
man body,  37°  C.  (98.6°  F.). 

The  range  between  the  minimum  and  maximum 
degrees  of  temperature  in  bacterial  resistance  is 
equally  great,  spores  being  much  more  resistant 
than  the  vegetative  forms;  some  spores  withstand- 
ing boiling  for  sixteen  hours,  while  the  vegetative 
forms  are  usually  killed  by  ten  minutes'  exposure 
to  60°  C.  (140°  F.)  with  moisture. 

By  thermal  death  point  is  meant  the  degree  of 
temperature  necessary  to  kill  the  organisms,  in  a 
given  time ;  and  as  this  varies  with  different  species, 
it  is  used  as  a  means  of  identification,  the  thermal 
death  point  of  all  of  the  common  species  being  well 
known. 

Light.  —  That  light  affects  the  activities  of  living 
cells  has  long  been  known;  the  effects  of  light  upon 
the  higher  forms  of  life  have  been  the  subject  of  much 
investigation  during  recent  years.  Sunlight  has  a 


PHYSICAL   AND   CHEMICAL   AGENTS  29 

germicidal  effect  upon  bacteria,  many  species  being 
killed  within  a  few  seconds  upon  exposure  to  the 
direct  rays  of  the  sun,  and  all  showing  different 
degrees  of  sensitiveness  to  light.  The  electric  light 
exerts  a  similar  effect  to  sunlight,  but  is  less  powerful. 

Moisture.  —  The  absence  of  moisture  may  cause 
the  death  of  bacteria  or  cause  a  suspension  of  de- 
velopment. Certain  species  are  deprived  of  the 
power  of  reproduction  without  moisture,  which  under 
favorable  conditions  will  again  grow  and  multiply. 

Desiccation  (drying)  destroys  nearly  all  of  the 
pathogenic  bacteria,  the  tubercle  bacillus  being 
one  of  the  most  resistant  to  drying  and  the  cholera 
spirillum  one  of  the  most  sensitive.  The  spores, 
however,  are  extremely  resistant  to  drying.  It  is 
said  that  the  spores  of  the  anthrax  bacillus  will 
survive  drying  for  ten  or  more  years. 

This  sensitiveness  to  drying,  shown  by  a  large 
majority  of  disease-germs,  would  indicate  that  infec- 
tion through  the  air,  cannot  be  so  common  as  had 
been  supposed. 

Oxygen.  —  In  their  relation  to  oxygen  bacteria 
are  divided  into  three  classes :  (1)  those  which  re- 
quire free  oxygen  for  the  maintenance  of  their 
activities,  called  obligatory  aerobes;  (2)  those  which 
do  not  grow  except  in  the  almost  entire  absence  of 


30  BACTERIOLOGY   FOR   NURSES 

free  oxygen,  called  obligatory  anaerobes;  and  (3)  the 
facultative  anaerobes,  which  may  exist  with  or  with- 
out oxygen. 

The  obligatory  anaerobes  derive  the  small  amount 
of  oxygen  necessary  to  them  from  the  oxygen  com- 
pounds of  the  material  in  which  they  are  growing. 

Food.  —  Bacteria  obtain  their  food  from  many 
diverse  substances,  organic  compounds  of  all  kinds 
serving  them.  Nitrogenous  substances  especially 
are  quickly  attacked  by  many  species,  as  may  be 
witnessed  in  the  rapid  decomposition  of  meats. 

Carbon,  nitrogen,  and  water  are  essential  for  the 
growth  of  both  bacteria  and  the  higher  plants,  but 
in  the  case  of  the  latter  both  carbon  and  nitrogen 
must  be  resolved  into  simpler  forms  before  absorption 
can  take  place ;  while  bacteria  obtain  these  elements 
as  already  prepared  in  complex  organic  material, 
either  animal  or  vegetable. 

Bacteria  differ  greatly  in  their  food  requirements, 
some  species  thriving  best  upon  a  concentrated  form 
of  nourishment,  and  others  requiring  only  a  limited 
amount  of  protein  substances. 

The  greater  number  of  bacteria  belong  to  the  class 
known  as  saprophytes,  which  find  their  food  in  dead 
organic  matter  and  cannot  exist  in  living  tissues ; 
parasites,  on  the  contrary,  as  the  name  indicates, 


PHYSICAL   AND    CHEMICAL   AGENTS  31 

exist  in  living  tissues,  certain  species  being  adapt- 
able to  either  condition,  which  are  known  as  facul- 
tative bacteria.  Nearly  all  of  the  disease-producing 
(pathogenic)  bacteria  belong  to  the  latter  class. 

Some  parasitic  species  are  unable  to  live  except 
in  the  living  tissues  of  certain  hosts,  as  the  leprosy 
bacillus,  which  does  not  grow  outside  of  the  human 
body ;  also,  the  ordinary  bacteria  found  in  the  soil 
and  water  cannot  be  grown  in  animal  tissues. 

The  activities  of  bacteria  are  so  rapid  and  complex 
that  profound  changes  are  produced  in  the  materials 
upon  which  they  grow  and  find  their  food.  The 
changes  which  we  know  as  fermentation  and  putre- 
faction are  due  to  the  saprophytic  bacteria,  while 
the  parasitic  forms  found  in  the  living  tissues  pro- 
duce the  changes  which  we  call  disease,  and  are 
frequently  the  cause  of  death. 

The  saprophytes,  acting  upon  the  highly  organized 
tissues  of  dead  animals  and  vegetables,  resolve 
them  into  the  simpler  elements,  water,  carbon  dioxide, 
and  ammonia,  in  which  form  they  are  appropriated 
as  nourishment  by  the  higher  plants.  The  higher 
plants  in  turn  furnish  food  for  the  animal  kingdom, 
and  thus  the  food  supply  is  used  over  and  over  again 
in  different  forms,  making  what  is  known  as  the 
food  cycle.  Were  it  not  for  bacterial  activity,  vege- 


32  BACTERIOLOGY   FOR  NURSES 

tation  would  be  robbed  of  its  supply  of  carbon  and 
nitrogen,  and  plant  life  would  be  speedily  ended, 
which  in  turn  would  deprive  the  animal  kingdom  of 
food  and  thus  life  would  no  longer  be  possible. 

A  highly  important  group  of  saprophytes  com- 
prises the  nitrifying  and  denitrifying  bacteria  which 
play  so  important  a  part  in  renewing  the  fertility 
of  the  soil. 

In  the  process  of  decomposition  which  goes  on 
through  bacterial  activity,  there  is  a  loss  of  consider- 
able nitrogen  into  the  air  where  it  is  no  longer  avail- 
able for  plant  food;  there  is  in  consequence  a 
constant  diminishing  of  nitrogen  food  for  vegetation. 
Also  there  is  a  loss  of  plant  food  by  drainage  into 
streams  and  the  sea,  which,  if  continued  without 
check,  would  so  deplete  the  soil  of  nitrogen  com- 
pounds that  plants  could  no  longer  live. 

It  is  this  loss  of  nitrogen  from  the  soil  which  forces 
the  farmer  to  apply  fertilizers  of  various  kinds  to 
renew  the  exhausted  soil. 

It  has  been  discovered,  however,  that  the  presence 
of  certain  bacteria  in  the  soil  insures  a  slow  but  sure 
gain  in  the  amount  of  nitrogen  compounds,  and 
sterile  fields  are  inoculated  by  the  application  of 
soil  containing  these  bacteria,  which  are  of  two  or 
three  species  working  together.  The  exact  process 


PHYSICAL  AND  CHEMICAL  AGENTS         33 

whereby  these  bacteria  restore  the  free  nitrogen  to 
the  soil  is  not  clearly  understood,  but  it  is  thought 
that  the  process  requires  the  combined  efforts  of 
several  species.  It  has  also  been  learned  that  the 
combined  action  of  certain  higher  plants  and  some 
species  of  bacteria  arrests  or  reclaims  the  free  nitro- 
gen. Ordinary  plants  do  not  absorb  the  free  nitro- 
gen from  the  atmosphere,  but  a  class  known  as 
legumes  —  to  which  clover,  peas,  and  beans  belong 
—  together  with  certain  soil  bacteria  is  able  to 
extract  the  free  nitrogen  from  the  air  which  per- 
meates the  soil;  the  evidences  of  which  are  small 
tubercles  or  nodules  growing  upon  the  roots,  which 
contain  nitrifying  bacteria  and  nitrogen  compounds. 
From  the  knowledge  of  this  nitrifying  process  has 
grown  the  practice  of  planting  sterile  fields  with 
legumes,  chiefly  clover  or  peas,  and  plowing  the  crop 
under  while  green,  which  restores  the  lost  nitrogen 
to  the  exhausted  soil. 

The  saprophytes  may  therefore  be  regarded  as 
benefactors,  while  the  parasites,  to  which  belong  the 
pathogenic  bacteria,  exist  at  the  expense  of  both 
animal  and  vegetable  life. 

The  Effect  of  Chemicals  upon  Bacteria.  —  Many 
species  of  bacteria  in  the  course  of  their  growth 
produce  acids  and  other  injurious  substances  which 


34  BACTERIOLOGY    FOR    NURSES 

arrest  further  multiplication.  The  chemical  prod- 
ucts of  the  various  species  may  be  favorable  or  in- 
jurious to  each  other. 

Chemical  Antiseptics  and  Disinfectants.  —  An  anti- 
septic retards  the  growth  but  does  not  kill  bacteria,  and 
a  disinfectant,  or  germicide,  destroys  the  organisms. 

By  sterilization  is  meant  the  complete  destruction 
of  all  bacteria,  and  all  processes *  which  sterilize 
necessarily  disinfect,  but  all  disinfecting  processes 
do  not  sterilize,  the  difference  being  that  in  steriliza- 
tion the  spores  are  also  destroyed. 

An  enormous  number  of  proprietary  disinfectants 
are  constantly  advocated  for  many  purposes,  but 
complete  disinfection  may  be  obtained  from  simple 
chemical  compounds  at  a  very  slight  comparative 
expense,  whereas  the  composition,  strength,  and 
effectiveness  of  patented  mixtures  are  unknown  and 
consequently  unreliable,  while  the  expense  is  great. 

Lime  is  one  of  the  oldest  disinfectants  known; 
mixed  with  water  to  the  consistency  of  cream,  it 
is  an  excellent  disinfectant  for  excreta  and  privy 
vaults.  By  the  addition  of  more  water  it  is  known 
as  whitewash,  and  is  the  best  practical  disinfectant 
for  cellars  or  rough  walls  of  any  kind,  in  houses, 
barracks,  stables,  and  other  outbuildings. 

1  Sterilization  by  steam,  etc.,  is  spoken  of  elsewhere. 


PHYSICAL    AND    CHEMICAL   AGENTS  35 

Lime  which  is  to  be  used  for  disinfecting  purposes 
should  be  freshly  slaked,  as  "  air-slaked  "  lime  has 
no  antiseptic  value.  It  is  said  that  a  20  per  cent 
solution  of  freshly  slaked  lime  mixed  with  half  its 
bulk  of  typhoid  excreta,  will  bring  about  complete 
disinfection  within  an  hour. 

Chlorinated  Lime  (Chlorid  of  lime)  has  also  long 
been  used  as  a  disinfectant,  and  is  especially  valuable 
for  the  disinfection  of  sewage  and  water.  For  cellars 
and  privies  it  is  used  as  a  dry  powder,  but  for  dis- 
infecting the  excreta  from  communicable  diseases  a 
solution  (6  ounces  to  a  gallon  of  water)  is  used ;  the 
same  solution  is  also  excellent  for  disinfecting  floors 
and  other  woodwork.  An  easy  method  of  disin- 
fecting drinking  water  is  to  add  1  gram  (15  grains) 
of  chlorinated  lime  to  1  liter  of  water,  and  after 
thorough  mixing  use  this  solution  in  the  proportion  of  1 
part  to  200,000  parts  of  water,  mix  well,  allow  to  stand 
20  minutes  and  the  water  may  be  regarded  as  safe. 

Sulphur  is  another  disinfectant  which  has  long  been 
in  use .  Sulphur  dioxide  is  produced  by  burning  the  sul- 
phur, the  process  being  known  as  sulphur  fumigation. 

The  value  of  sulphur  fumigation  depends  upon  the 
presence  of  moisture,1  dry'- fumigation  being  practically 

1  One  fifth  pound  of  water  to  each  pound  of  sulphur  should 
be  allowed  to  each  250  cubic  feet  of  air  space. 


36  BACTERIOLOGY   FOR   NURSES 

useless  except  for  the  destruction  of  mosquitoes  and 
bedbugs,  which  may  be  carriers  of  disease  germs. 

Sulphur  fumigation  with  moisture  will  not  destroy 
spore-bearing  bacteria  of  any  kind. 

Sulphur  fumes  tarnish  all  metals  and  discolor 
most  fabrics. 

Permanganate  of  potassium  is  used  for  disinfecting 
the  hands  in  surgical  work. 

Copper  sulphate  is  used  (1 : 1,000,000)  for  the 
destruction  of  the  microscopic  algae  in  large  water 
supplies. 

Bichloride  of  mercury  (corrosive  sublimate)  is 
probably  the  most  important  chemical  disinfectant 
known,  although  for  some  purposes  it  cannot  be  used. 
It  corrodes  all  metals  and  therefore  cannot  be  used 
upon  surgical  instruments  nor  plumbing  fixtures. 
Neither  can  bichloride  of  mercury  be  used  for  the 
disinfection  of  excreta  or  other  organic  matter,  as  it 
combines  with  the  albuminous  substances  and  pro- 
duces an  inert  compound  which  has  no  effect  upon 
the  bacteria.  The  standard  solution  1 : 1000  bi- 
chloride of  mercury  is  used  for  disinfecting  the  skin 
and  for  washing  floors  and  other  woodwork  and 
furniture  after  an  infectious  illness. 

Carbolic  acid  (phenol)  one  of  the  best-known 
disinfectants,  is  a  substance  derived  from  coal  tar, 


PHYSICAL    AND    CHEMICAL   AGENTS  37 

the  crude  acid  being  considered  a  more  effectual 
disinfectant  than  the  more  refined  grades.  Carbolic 
acid  does  not  corrode  metals,  and  "  in  a  5  per  cent 
solution  will  destroy  all  vegetative  bacteria  and 
most  spores  even  in  the  presence  of  considerable 
organic  matter."  (Jordan.)  Its  germicidal  power  is 
greatly  increased  by  heat,  experiment  showing  that 
at  room  temperature  a  5  per  cent  solution  was  not 
effective  against  anthrax  spores  in  thirty-six  days, 
while  at  55°  C.  (131°  F.)  it  was  successful  in  two 
hours,  and  at  75°  C.  (167°  F.)  in  three  minutes. 

The  cresols  are  substances  contained  in  crude 
carbolic  acid  which  are  used  very  satisfactorily  in 
surgical  work,  the  best-known  preparations  being 
creolin,  crenosol,  and  lysol. 

Alcohol  is  much  used  as  a  disinfectant  in  surgical 
work,  although  of  doubtful  value,  and  is  also  used  for 
the  preservation  of  organic  substances. 

Soaps  of  all  kinds  are  disinfectant  and  antiseptic. 
It  has  been  demonstrated  that  a  10  per  cent  solution 
of  good  soap  would 'destroy  the  bacilli  of  typhoid 
fever,  a  stronger  solution  being  necessary  for  cholera 
bacilli ;  but  for  pus  germs,  streptococci  and  staphylo- 
cocci,  a  20  per  cent  solution  was  entirely  ineffective. 

For  practical  purposes,  however,  a  soap  solution 
could  not  be  the  sole  disinfectant  used  for  the  bed 


38  BACTERIOLOGY    FOR   NURSES 

and  body  linen  of  patients  suffering  from  contagious 
diseases,  as  the  procedure  in  ordinary  laundries  would 
not  insure  certain  results,  and,  again,  such  linen 
must  be  wet  with  some  chemical  disinfectant  imme- 
diately upon  its  removal  from  the  bed,  as  a  protection 
to  the  nurses  and  laundresses  who  must  handle  it, 
and  to  prevent  any  contagious  matter  from  blowing 
about  as  dust.  The  tincture  of  green  soap  is  used 
almost  exclusively  in  all  hospitals  for  the  cleaning  of 
hands  and  the  field  of  operation,  it  being  conceded 
to  be  the  best  soap  known  for  the  purpose. 

The  value  of  soap  in  the  process  of  room  or  house- 
hold disinfection  is  not  wholly  realized. 

Corrosive  sublimate,  carbolic  acid,  and  many  other 
disinfectants  used  upon  fine  furniture  and  woodwork, 
in  solutions  strong  enough  to  be  good  disinfectants, 
are  destructive  to  the  finish,  but  a  20  per  cent  solu- 
tion of  warm  soapsuds  to  which  has  been  added 
1  ounce  of  petroleum  to  each  gallon,  may  be  used 
upon  the  finest  mahogany  surfaces  with  no  injury ; 
which  would  appear  to  be  a  much  more  effective 
disinfection  than  merely  wiping  the  furniture  with 
a  cloth  damp  with  corrosive  sublimate  or  other 
chemical  disinfectant.  The  addition  of  an  ounce  of 
washing  soda  to  each  gallon  of  hot  soapsuds,  used 
upon  floors  after  an  infectious  illness  or  in  case  of 


PHYSICAL    AND    CHEMICAL    AGENTS  39 

very  dirty  wooden  floors  will  not  only  remove  but 
disinfect  the  filth. 

The  commercial  medicated  soaps  are  said  to  be 
of  little  value.  Abbott  gives  a  formula  for  carbol- 
soap  which  has  the  same  disinfectant  value  as  pure 
carbolic  acid,  is  easily  made,  and  particularly  valu- 
able for  the  disinfection  of  washable  clothing :  — 
Dissolve  3  parts  green  soap  in 

100  parts  of  warm  water,  add 
5  parts  commercial  carbolic  acid,  stirring 
slowly. 

Formaldehyde  is  a  gas  which,  dissolved  in  water, 
gives  a  solution  of  about  40  per  cent  formaldehyde, 
called  formalin.  Formalin  is  the  preparation  com- 
monly used  for  disinfecting  purposes. 

Formaldehyde  is  considered'  the  most  valuable 
known  disinfectant  for  room  disinfection  following 
all  infectious  diseases ;  it  is  also  a  deodorizer ;  it  does 
not  tarnish  metals  nor  discolor  fabrics,  and  the  gas 
is  not  poisonous,  although  extremely  irritating. 

In  fumigating  with  formalin  all  cracks  and  crevices 
must  be  tightly  packed.  There  are  several  especially 
designed  lamps  and  generators  in  use,  the  principle 
of  all  being  to  liberate  the  gas  by  heat,  but  except 
for  hospitals  or  other  large  institutions  they  are  too 
expensive  for  general  use  and  the  simple  method  of 


40  BACTERIOLOGY    FOR    NURSES 

pouring  formalin  over  permanganate  of  potassium 
in  an  open  vessel,  which  causes  the  liberation  of  an 
immense  volume  of  gas,  is  more  commonly  employed. 
For  each  1000  cubic  feet  of  space  at  15.5°  C.  (60° 
F.)  use:- 

Formaldehyde,  40  per  cent,  16  ounces, 
Potassium  permanganate,  6f  ounces. 
The  vessel  should  allow  not  less  than  12  quarts 
for  this  amount.     This  process  has  the  advantage  of 
being  easily  multiplied  for  large  spaces,  which  is 
not  the  case  with  single  lamps  or  generators. 

The  formaldehyde  should  not  be  added  until  the 
last  moment  before  leaving  and  sealing  the  room. 
When  it  is  impossible  to  leave  a  room  open  for 
twenty-four  hours  after  fumigation  with  formalde- 
hyde, the  odor  may  be  quickly  removed  by  placing 
a  shallow  vessel  (platter)  filled  with  aqua  ammonia 
in  the  room. 

Disinfection  of  Infective  Materials. 
Excreta :  Carbolic  acid,  5  per  cent ; 

or  Chloride  of  lime,  2  per  cent ; 
or  Milk  of  lime  (lime  and  water,  consist- 
ency of  cream) ; 

or  Bichloride  of  mercury,  1  ounce, 
Hydrochloric  acid,  10  ounces, 
Water,  1  gallon. 


PHYSICAL    AND    CHEMICAL    AGENTS  41 

In  all  cases  the  disinfecting  solution  should  be 
double  the  excreta  in  bulk,  and  the  mixture,  closely 
covered,  be  allowed  to  stand  some  time  before 
emptying. 

All  vessels  used  for  stools,  sputum,  and  vomit 
should  be  washed  in  carbolic  acid  5  per  cent,  fol- 
lowed by  scrubbing  in  hot  soapsuds  and  by  boiling 
in  soda  solution  3  per  cent. 

Clothing.  —  Bed  and  body  linen,  towels,  napkins, 
wash  curtains,  bureau  and  stand  covers,  soak  in 
cold  carbol-soap  solution  (p.  39)  for  two  hours, 
rinse  in  clear  cold  water,  and  put  into  the  laundry. 

Woolen  garments,  unless  badly  infected,  may 
be  fumigated  with  formaldehyde  followed  by  ex- 
posure to  sunlight.  Otherwise,  heavy  garments, 
carpets,  rugs,  furs,  woolen  curtains,  together  with 
children's  playthings  and  books,  should  be  put  into 
compact  bundles  wrapped  in  cloths  wet  in  carbolic 
acid  5  per  cent,  or  bichloride  of  mercury  1 : 1000, 
and  burned  in  a  furnace.1 

Utensils.  —  Dishes  and  silver  may  be  boiled  for 
20  minutes  in  soda  solution  5  per  cent,  also  wash- 
basins and  other  toilet  dishes,  besides  all  surgical 
instruments,  nail  files,  and  manicure  scissors. 

1  In  the  light  of  more  recent  experiments  the  necessity  for 
the  complete  destruction  of  such  articles  is  disputed. 


42  BACTERIOLOGY    FOR    NURSES 

Toothbrushes  should  not  be  used  during  infectious 
illness,  but  the  mouth  and  teeth  cleaned  with  small 
mouth  sponges  and  toothpicks  wrapped  with  ab- 
sorbent cotton,  both  to  be  burned  immediately. 

Furniture.  —  1.  Fumigation  with  formaldehyde. 

2.  Wipe  with  cloth  wet  in  carbolic  acid  5  per  cent, 
followed  by  washing  with  20  per  cent  warm  soap- 
suds containing  1  ounce  of  petroleum  to  each  gallon. 

3.  Expose  to  sunlight  for  several  days  in  succes- 
sion if  possible,  turning  all  sides  to  the  sun;   turn 
upside  down  as  well. 

Walls.  —  1.  If  papered,  wet  thoroughly  with  bi- 
chloride of  mercury  solution,  1 : 1000,  remove  paper, 
being  very  careful  to  keep  the  paper  wet. 

2.  Fumigate  the  room  and  follow  by  opening  all 
windows  and  doors  for  twenty-four  hours. 

Floors.  —  1.  Wet  with  bichloride  of  mercury  so- 
lution 1 : 1000  before  fumigation. 

2.  After  fumigation,  scrub  with  20  per  cent  hot 
soapsuds  to  which  has  been  added  1  ounce  of  washing 
soda  to  each  gallon.  This  first  cleaning  should  be 
done  with  a  broom  and  mop,  that  the  water  may  be 
as  near  boiling  as  is  possible. 

Woodwork.  —  1.  Wet  with  bichloride  of  mercury 
1 : 1000  before  fumigation. 

2.  After  fumigation,  wash  as  directed  for  furniture. 


PHYSICAL    AND    CHEMICAL    AGENTS  43 

THE    EFFECTS   OF   BACTERIAL   GROWTH 

As  before  stated,  bacterial  growth  is  so  rapid  and 
complex  that  profound  changes  always  result  in  the 
structure  and  composition  of  the  materials  upon 
which  the  bacteria  are  developing.  The  putrefac- 
tive change  which  takes  place  in  the  body  soon  after 
death,  due  to  the  invasion  of  bacteria,  is  a  familiar 
example. 

Physical  Effects.  Heat.  —  The  temperature  of 
organic  substances  undergoing  the  process  of  de- 
composition is  often  very  much  higher  than  the 
surrounding  atmosphere,  as  in  the  heating  of  damp 
hay  or  in  manure  heaps,  both  of  which  are  attributed 
to  heat-producing  (thermogenic)  bacteria. 

Light-producing  (photogenic)  bacteria  cause  the 
phosphorescence  sometimes  observed  upon  decaying 
fish,  meat,  or  wood  and  more  commonly  in  sea  water. 

Chemical  Products.  —  The  chemical  products  of 
bacteria  may  arise  from  their  secretions  or  excretions 
or  from  the  products  resulting  from  their  action  upon 
food  substances,  the  character  of  which  depends  upon 
the  chemical  contents  of  the  food  itself  and  the 
species  of  bacteria  concerned.  It  is  believed  that 
most  of  the  chemical  changes  wrought  by  bacterial 
activity  are  not  the  direct  action  of  the  organisms 


44  BACTERIOLOGY   FOR   NURSES 

themselves,  but  arise  from  the  enzymes  or  ferments 
produced  by  them.  A  single  organism  may  secrete 
more  than  one  enzyme,  depending  upon  different 
conditions  of  food  and  temperature. 

By  usage  the  term  putrefaction  is  used  to  designate 
the  disintegration  (breaking  up)  of  proteid  sub- 
stances, while  fermentation  is  used  to  denote  the  dis- 
integration of  the  carbohydrates.  The  bacteria 
which  produce  putrefaction  are  known  as  saprogenic, 
and  those  concerned  in  fermentations,  as  in  the  lactic 
and  butyric  acids  in  milk,  butter,  cheese,  and  vine- 
gars, are  known  as  zymogenic.  Bacterial  activity 
produces  both  acids  and  alkalies ;  the  fermentation  of 
carbohydrates  producing  an  acid  reaction,  and  the 
putrefaction  of  proteid  substances  causing  an  alka- 
line reaction.  In  the  putrefaction  of  nitrogenous 
substances  there  is  not  only  a  complete  change  in 
the  form  of  the  material  but  the  production  of 
many  gases  of  peculiarly  offensive  odor,  which  are 
believed  to  be  due  to  the  action  of  the  obligatory 
anaerobes. 

Chromogenic  bacteria  are  those  which  produce 
color,  the  significance  of  the  pigment  being  little 
understood. 

Ptomains  and  Toxins.  —  The  poisonous  products 
of  bacteria  are  known  as  ptomains  and  toxins ; 


PHYSICAL  AND  CHEMICAL  AGENTS         45 

ptomains  being  the  poisonous  products  resulting 
from  the  action  of  bacteria  in  the  decomposition  of 
organic  matter,  and  toxins  are  the  poisonous  sub- 
stances produced  by  the  bacteria  themselves. 

Many  epidemics  of  food  poisoning  which  were 
formerly  attributed  to  ptomains  are  now  believed  to 
be  due  to  the  presence  of  some  special  organism. 

Pathogenic  bacteria  produce  disease  by  their 
action  upon  the  animal  tissues  in  which  they  find 
lodgment ;  this  poisonous  action  may  be  due  to  the 
toxins  produced  by  the  bacteria,  or  to  the  poisonous 
material  of  which  the  germs  are  composed  (endo- 
toxins).  Some  species  produce  soluble  poisons 
which  are  easily  separated  from  the  organisms  them- 
selves, while  others  are  found  to  contain  proteid 
matters  in  their  own  bodies  which  are  highly  toxic, 
and  these  we  know  as  endotoxins. 

The  potency  (strength)  of  some  of  the  bacterial 
toxins  far  exceeds  that  of  any  other  known  poisons ; 
for  instance,  the  toxin  produced  by  the  bacillus  of 
tetanus  (lockjaw)  is  more  than  a  thousand  times  as 
powerful  as  strychnine. 


CHAPTER  V 

THE   RELATIONS   OF   BACTERIA   TO    DISEASE 

AMONG  the  earliest  records  of  history  theories  re- 
garding the  causes  of  disease  may  be  found.  The 
belief  that  the  sick  man  was  possessed  of  the  devil 
seems  to  have  been  the  first  and  most  lasting  belief, 
for  it  is  still  held  by  the  savage  races,  and  may  be 
found  among  the  ignorant  classes  of  civilized  nations, 
who  hold  it  to  be  the  cause  of  insanity. 

During  the  middle  ages,  when  men  began  to  study 
the  structure  and  composition  of  the  body,  the  Hip- 
pocratic  theory  that  the  body  contained  four  hu- 
mors, viz.  blood,  phlegm,  and  black  and  yellow 
bile,  which  worked  in  harmony  in  health,  but  lost 
their  proportion  in  disease,  was  the  generally  ac- 
cepted belief  as  the  cause  of  disease ;  but  the  reasons 
for  the  loss  of  proper  proportion  were  not  stated. 

Later  many  vague  speculations,  based  more  upon 
imagination  than  upon  facts,  prevailed,  until  Pas- 
teur's investigations  into  bacteria  as  a  cause  for  fer- 
mentations led  to  his  discoveries  and  proofs  that  the 
infectious  diseases  owed  their  origin  to  bacteria. 

46 


THE    RELATIONS    OF    BACTERIA    TO    DISEASE  47 

At  the  present  time  the  principal  diseases  known 
to  be  due  to  specific  microorganisms  are  :  — 

Class  I.  Septicaemia,  gonorrhoea,  Asiatic  cholera, 
leprosy,  pyaemia,  syphilis,  influenza,  bubonic  plague, 
pneumonia,  diphtheria,  tetanus,  relapsing  fever, 
meningitis,  typhoid  fever,  tuberculosis,  glanders, 
anthrax,  malaria,  sleeping-sickness. 

Class  II.  To  this  class  belong  those  diseases 
caused  by  organisms  which  are  yet  unknown  :  small- 
pox, foot-and-mouth  disease,  yellow  fever,  chicken 
pox,  hydrophobia  (rabies),  measles,  mumps,  scarlet 
fever,  Rocky  Mountain  spotted  fever,  typhus  fever, 
epidemic  infantile  paralysis. 

The  sources  of  the  communicable  diseases  in 
man  are  man  himself  and  the  lower  animals;  the 
majority  are  peculiar  to  human  beings,  although 
we  contract  anthrax  from  cattle,  plague  from  rats, 
tuberculosis  in  part  from  cattle,  etc.  Formerly  it 
was  thought  that  the  main  sources  of  infection  in 
man  were  in  water,  air,  soil,  and  food;  and  while 
these  may  serve  as  vehicles  for  conveying  infectious 
materials,  the  source  is  usually  in  man  himself. 

No  single  species  of  pathogenic  bacteria  can  pro- 
duce disease  in  all  animals,  nor  are  the  disease- 
producing  bacteria  for  animals  the  cause  of  disease 
in  plants.  A  bacterium  may  produce  disease  in 


48  BACTERIOLOGY   FOR   NURSES 

man  and  be  harmless  for  cattle,  and  on  the  con- 
trary, man  is  not  susceptible  to  all  the  diseases  of 
cattle. 

The  tissues  of  animals  and  plants  which  afford 
favorable  soil  for  the  growth  and  multiplication  of 
bacteria  are  known  as  the  hosts,  and  the  host  may 
not  always  favor  bacterial  activity ;  thus  an  adult 
is  usually  resistant  to  the  so-called  children's  dis- 
eases, and  on  the  other  hand,  hunger,  thirst,  excessive 
fatigue,  and  the  wasting  diseases  all  lessen  the  body's 
resistance  and  render  the  individual  susceptible  to 
infections  of  all  kinds.  The  virulence  (ability  to 
produce  disease)  of  the  microorganisms  also  varies, 
and  infection  may  depend  upon  the  number  of  bac- 
teria introduced  into  the  body,  and  so  it  may  be  said 
that  the  virulence  and  number  of  the  invading  bac- 
teria vary  quite  as  much  as  the  susceptibility  of  the 
host. 

The  channels  by  which  infection  may  enter  the 
body  are  (a)  by  the  respiratory  tract,  (fe)  by  the  di- 
gestive tract,  and  (c)  through  the  skin.  It  is 
thought  that  90  per  cent  of  all  infections  is  taken 
into  the  body  through  the  nose  and  mouth,  and  as 
we  are  usually  responsible  for  what  goes  into  our  own 
mouths,  it  may  be  seen  that  it  behooves  us  to  observe 
hygienic  personal  habits. 


THE    RELATIONS    OF    BACTERIA   TO   DISEASE  4ft 

Character  of  Infections.  —  "In  the  production 
of  disease  by  microorganisms  there  are  two  main 
factors  involved,  namely,  (a)  the  multiplication  of  the 
living  organisms  after  they  have  entered  the  body, 
and  (6)  the  production  by  them  of  poisons  which 
may  act  both  upon  the  tissues  around,  and  upon  the 
body  generally.  The  former  corresponds  to  infec- 
tion, and  the  latter  is  of  the  nature  of  intoxication 
or  poisoning.  In  different  diseases  one  of  these  is 
usually  the  more  prominent  feature,  but  both  are  al- 
ways more  or  less  concerned."  (Muir  and  Ritchie.) 

Infections  vary  widely  in  the  effects  produced  in 
the  body,  both  in  the  local  and  general  or  constitu- 
tional symptoms. 

Certain  diseases  are  known  as  toxcemic,  that  is, 
the  blood  contains  the  poisonous  products  (toxins) 
of  the  invading  bacteria.  Tetanus  is  notably  a 
toxsemic  disease,  the  local  symptoms  being  almost 
entirely  absent,  and  no  bacteria  are  found  in  the 
blood,  while  the  constitutional  effects  are  profound 
and  nearly  always  fatal. 

Diphtheria  is  also  a  characteristic  toxsBmic  in- 
fection, although  the  local  symptoms  are  pronounced 
as  well. 

Septiasmidj  or  bacteremia  as  it  is  sometimes  called, 
denotes  the  presence  and  multiplication  of  bacteria 


50  BACTERIOLOGY    FOR   NURSES 

in  the  blood.  Typhoid  fever,  pneumonia,  and  the 
general  pus  infections  known  as  "  blood-poisoning  " 
belong  to  this  class,  the  bacteria  being  found  in  the 
blood  or  in  special  organs. 

Pycemia  is  a  condition  following  profound  infec- 
tions, as  septicaemia,  in  which  many  abscesses  are 
formed  throughout  the  body. 

Secondary  infections  are  those  which  gain  entrance 
to  the  body  through  the  lesions  produced  by  some 
other  organism,  as  typhoid  fever  followed  by  pneu- 
monia, or  measles  followed  by  tuberculosis,  or  scarlet 
fever  followed  by  diphtheria ;  diabetes  is  frequently 
accompanied  by  pus  infection  of  a  serious  character ; 
in  fact,  all  wasting  diseases  lower  the  resistance  of  the 
body  and  greatly  increase  the  susceptibility  to  infec- 
tions of  all  kinds. 

The  Defenses  of  the  Body.1  —  The  unbroken  skin 
is  usually  impassable  to  bacteria.  Virulent  organ- 
isms are  often  found  upon  the  skin  of  perfectly 
healthy  persons,  where  they  appear  to  be  harmless 
unless  an  abrasion  occurs,  which  affords  an  entrance 
into  the  deeper  tissues.  The  mucous  membranes 
would  prove  favorable  sites  for  the  growth  of  bacteria 
were  it  not  for  the  frequent  removal  of  the  mucus 
which  they  secrete ;  the  mouth  of  a  healthy  person 
1  See  Immunity,  p.  54. 


THE   RELATIONS    OF    BACTERIA   TO    DISEASE  51 

contains  large  numbers  of  bacteria  of  all  kinds,  — 
the  bacilli  of  diphtheria,  of  influenza,  and  the 
pneumococci  are  often  present,  —  but  the  saliva  has 
a  slight  germicidal  power  and  serves  as  a  constant 
wash  to  the  membranes  of  the  mouth;  the  hairs 
of  the  nasal  and  aural  passages  and  the  eyelashes 
make  some  obstruction  to  the  entrance  of  bacteria ; 
and  the  moist  surfaces  of  the  air-passages  retain 
most  of  the  bacteria  contained  in  the  air  before  it 
reaches  the  lungs.  The  hydrochloric  acid  of  the 
gastric  juice  is  unfavorable  for  the  growth  of  bacteria, 
although  it  does  not  always  kill  them ;  the  bacillus 
of  typhoid  fever,  for  instance,  passes  through  the 
stomach  and  finds  favorable  conditions  for  develop- 
ment in  the  intestines. 

Large  numbers  of  bacteria  are  found  in  the  intes- 
tines of  all  perfectly  healthy  persons,  but  unless 
resistance  is  lowered  from  some  cause,  no  manifesta- 
tion of  disease  occurs. 

Transmission  of  Disease.  —  Infectious  diseases 
are  transferred  either  directly  (contact)  from  a 
patient  to  another  individual,  or  indirectly  through 
air,  water,  food,  or  carried  by  insects. 

As  a  rule,  the  pathogenic  bacteria  are  incapable  of 
living  except  for  a  very  short  time  apart  from  the 
body,  but  the  fact  that  they  may  exist  for  a  con- 


52  BACTERIOLOGY   FOR   NURSES 

siderable  length  of  time  upon  the  bodies  of  healthy 
persons,  and  by  them  be  transmitted  to  those  who 
are  susceptible  to  infections,  constitutes  a  serious 
menace.  The  bacillus  of  influenza  exists  but  a  very 
short  time  apart  from  its  human  host,  but  the  bacilli 
of  tuberculosis  and  of  typhoid  fever  are  much  more 
resistant,  adapting  their  existence  to  other  conditions. 

Infectious  materials  are  thrown  off  from  the  body 
through  the  discharges  from  the  nose,  the  mouth, 
the  intestines,  the  bladder,  and  the  skin  during  the 
course  of  infectious  diseases,  and  are  often  found  in 
these  tracts  and  in  the  excreta  long  after  the  patients 
have  seemingly  entirely  recovered ;  this  condition  is 
notable  in  diphtheria,  scarlet  fever,  and  typhoid 
fever,  and  such  persons  are  known  as  "  carriers." 

The  modes  by  which  infectious  materials  are 
carried  from  one  person  to  another  are  at  the  present 
time  subjects  for  much  discussion,  and  it  seems  to 
be  the  consensus  of  opinion  that  "  contact  "  infection 
is  much  more  frequent  than  was  formerly  supposed. 
Contact  does  not  necessarily  imply  the  actual  con- 
tact of  the  sick  and  the  well ;  for  instance,  the 
child  with  diphtheria  may  leave  infectious  material 
upon  the  drinking  cup,  or  a  clean  wound  may  become 
infected  by  contact  with  hands  which  carry  infectious 
material. 


THE    RELATIONS    OF   BACTERIA   TO    DISEASE  53 

Contact  infection  is  the  chief  source  of  danger  in 
those  communicable  diseases  in  which  infectious 
materials  are  discharged  from  the  nose  and  throat, 
such  as  tuberculosis,  diphtheria,  measles,  pneumonia, 
influenza,  scarlet  fever,  whooping  cough;  and  also 
in  those  diseases  in  which  the  infectious  materials 
are  discharged  in  the  urine  and  feces,  as  in  typhoid 
fever,  dysentery,  and  cholera. 


CHAPTER  VI 

IMMUNITY 

BY  immunity  is  meant  non-susceptibility  to  a  given 
disease  or  organism;  thus  a  yellow  fever  immune 
is  a  person  who  is  not  susceptible  to  yellow  fever. 

Immunity  may  be  natural  or  acquired. 

Natural  Immunity.  —  Man  is  susceptible  to  infec- 
tion with  many  microorganisms,  some  of  which  are 
harmless  to  the  lower  animals,  and  thus  it  is  said  that 
these  animals  possess  a  natural  immunity  to  these 
infections.  The  bacillus  of  typhoid  fever  produces 
serious  disturbances  in  man,  but  rarely  any  in 
cattle,  and  the  cold-blooded  animals  are  not  suscep- 
tible to  tetanus,  which  in  man  and  the  higher  ani- 
mals is  a  serious  infection. 

The  physical  differences  existing  between  the 
warm  and  cold  blooded  animals,  the  vertebrates 
and  invertebrates,  and  many  other  distinctions  in 
the  various  groups  of  animals,  may  all  be  taken  into 
account  in  the  consideration  of  natural  immunity. 

It  was  formerly  held  that  certain  races  of  men 
54 


IMMUNITY  55 

were  susceptible  and  others  immune  to  certain  dis- 
eases, but  the  line  is  now  less  sharply  drawn  and 
differences  are  attributed  more  to  differences  of 
habits,  pursuits,  and  opportunities  for  infection 
than  to  racial  characteristics.  Individuals  vary 
greatly  in  their  powers  of  resistance,  and  members  of 
the  same  family  subject  to  the  same  environment 
often  exhibit  marked  differences  in  their  susceptibil- 
ity to  disease.  Epidemics  of  typhoid  fever  afford 
excellent  examples  of  the  natural  immunity  of  cer- 
tain persons;  for  while  all  may  use  the  same  polluted 
water,  not  all  are  infected. 

It  is  said  that  the  small  animals  used  in  the  bacte- 
riological laboratories  exhibit  the  same  individual 
differences  to  a  less  degree. 

Acquired  immunity  may  be  active  or  passive. 
Active  immunity  is  due  to  the  direct  participation 
of  the  organism  concerned,  as  immunit}^  to  smallpox 
is  acquired  by  an  attack  of  the  disease. 

Passive  immunity  is  acquired  by  the  transfer  of 
protective  substances  formed  in  the  body  of  another 
animal  to  the  body  of  the  person  to  be  protected. 
The  protection  afforded  by  the  use  of  diphtheria 
antitoxin  is  an  example  of  immunization  by  bac- 
terial products;  the  horse  is  actively  immunized  by 
the  repeated  injection  of  increasing  doses  of  diph- 


56  BACTERIOLOGY   FOR   NURSES 

theria  toxin  for  several  weeks,  or  until  the  blood 
contains  the  diphtheria  antitoxin,  which,  when 
injected  in  suitable  quantities  into  the  body  of  a 
person  who  has  been  exposed  to  diphtheria,  affords 
a  protection  against  the  disease.  The  antitoxin  of 
diphtheria  is  also  used  as  a  curative  measure. 

The  accompanying  table  from  Muir  and  Ritchie 
shows  the  chief  methods  by  which  artificial  immu- 
nity may  be  produced,  the  principles  underlying  all 
being  the  same :  — 

ARTIFICIAL  IMMUNITY 

A.  Active  Immunity  —  i.e.  produced  in  an  animal  by  an  injec- 
tion, or  by  a  series  of  injections,  of  non-lethal  doses  of  an 
organism  or  its  toxins. 
1.  By  injection  of  the  living  organisms. 

(a)  Attenuated  in  various  ways.     Examples:  — 

(1)  By  growing  in  the  presence  of  oxygen,  or  in  a 

current  of  air. 

(2)  By  passing  through  the  tissues  of  one  species  of 

animal  (becomes  attenuated  for  another  species). 

(3)  By  growing  at  abnormal  temperatures,  etc. 

(4)  By  growing  in  the  presence  of  weak  antiseptics, 

or  by  injecting  the  latter  along  with  the  organ- 
ism, etc. 
(6)  In  a  virulent  condition,  in  non-lethal  doses. 

2.  By  injection  of  the  dead  organisms. 

3.  By  injection  of  filtered  bacterial  cultures,  i.e.  toxins;  or  oj 

chemical  substances  derived  from  such  filtrates. 
These  methods  may  also  be  combined  in  various  ways. 


IMMUNITY  57 

B.  Passive  Immunity,  i.e.  produced  in  one  animal  by  injection 
of  the  serum  of  another  animal  highly  immunized  by  the 
methods  of  A. 

1.  By  antitoxic  serum,  i.e.  the  serum  of  an  animal  highly 

immunized  against  a  particular  toxin. 

2.  By  antibacterial  serum,  i.e.  the  serum  of  an  animal  highly 

immunized  against  a  particular  bacterium  in  the  living 
and  virulent  condition. 

The  Mechanism  of  Immunity.  —  The  study  of  the 
mechanism  of  immunity,  that  is,  the  process  which 
occurs  within  the  body  as  a  defense  against  the  in- 
vading bacteria,  has  been  enormous  and  presents 
problems  too  abstruse  and  complex  for  the  under- 
standing of  any  but  the  scientists  themselves.  As  a 
result  of  these  researches,  which  involve  such  industry, 
application,  patience,  and  profound  learning  that  we 
stand  amazed  at  their  depth,  there  has  grown  to  be 
more  or  less  well-defined  theories  of  the  mechanism 
of  immunity,  although  the  most  learned  among  the 
investigators  hesitates  the  least  to  admit  the  limits 
of  this  knowledge. 

Antitoxins.  —  In  1890  Behring  and  Kitasato  dis- 
covered that  if  the  blood-serum  of  an  immunized 
animal  was  combined  with  an  appropriate  amount 
of  toxin  (in  this  case  tetanus),  and  the  com- 
bination injected  into  a  susceptible  animal,  there 
was  neither  death  nor  infection;  in  other  words, 


58  BACTERIOLOGY   FOR  NURSES 

the  blood-serum  of  the  immune  animal  contained 
some  substance  which  neutralized  the  toxin,  render- 
ing it  harmless;  they  named  this  something  anti- 
toxin. 

The  chemical  character  of  antitoxin  is  still  a  matter 
of  conjecture,  but  it  has  been  proven  that  the  com- 
bination of  toxin  and  antitoxin  is  of  a  chemical 
nature,  the  antitoxin  holding  the  poison  of  the  toxin 
in  abeyance  (that  is,  neutralizing)  so  long  as  the 
combination  exists.  This  fact  has  been  repeatedly 
proved  in  the  laboratory,  where  it  is  possible  to 
control  both  substances  as  to  amount  and  environ- 
ment, but  it  is  easy  to  appreciate  how  difficult  the 
study  becomes  when  the  body  is  invaded  by  an 
unknown  quantity  of  pathogenic  bacteria,  and 
when  the  reaction  of  the  living  tissues  cannot  be 
definitely  gauged. 

It  has  been  found  that  antitoxin  in  small  amounts 
occurs  in  the  normal  blood  of  many  healthy  persons, 
and  that  the  amount  is  quickly  increased  when  toxic 
materials  are  introduced  into  the  body,  thus  showing 
that  the  presence  of  the  bacteria  stimulates  the 
manufacture  of  antitoxin  by  the  body.  It  is  be- 
lieved that  the  body- cells  are  responsible  for  the 
origin  of  the  antitoxin,  and  the  different  cells  are 
the  origin  of  the  antitoxins  for  different  organisms. 


IMMUNITY  59 

It  is  supposed  that  in  active  immunity,  i.e.  when  due 
to  virulent  organisms,  the  body-cells  continue  to 
maintain  the  antitoxin  above  the  normal;  while  in 
passive  immunity,  i.e.  when  due  to  antitoxin  serum 
taken  from  an  immunized  animal,  that  the  antitoxin 
is  eliminated  from  the  body  after  a  certain  time, 
and  the  body-cells  are  not  stimulated  to  continued 
activity.  This  condition  is  notable  following  the 
administration  of  diphtheria  antitoxin,  immunity 
lasting  about  three  weeks. 

It  might  be  supposed  the  presence  of  antitoxin, 
or  the  ability  of  the  body-cells  to  produce  it,  would 
be  sufficient  defense  against  disease-producing  bac- 
teria, but  there  seems  to  be  at  times  what  is  known 
as  a  chemical  affinity  (chemiotaxis)  between  the 
toxins  and  the  tissues  of  the  body,  in  which  the 
toxins  combine  with  the  body-cells  instead  of  with 
the  antitoxin,  which  causes  the  death  of  the  cells. 

Bactericidal  (ability  to  destroy)  Substances. — The 
blood  can  not  only  neutralize  bacterial  toxins,  but 
can  destroy  the  bacteria;  it  is  said  that  a  single  drop 
of  rabbit  blood  may  destroy  over  fifty  thousand 
anthrax  bacilli. 

The  natural  immunity  of  animal  organisms  was 
thought  by  Buchner  and  others  to  be  due  to  the 
bactericidal  substances  in  the  blood,  called  by  them 


60  BACTERIOLOGY    FOR    NURSES 

alexines,  and  the  degree  of  immunity  was  dependent 
upon  the  amount  of  alexines  contained  in  the  blood; 
but  it  has  been  found  that  in  some  cases  there  is  no 
relation  between  the  resistance  of  the  animal  and  the 
bactericidal  power  of  its  blood-serum.  The  human 
blood-serum  is  strongly  bactericidal  for  the  bacillus 
of  typhoid  fever,  but  that  fact  does  not  always  pre- 
vent the  multiplication  of  the  organism  in  the  blood 
during  an  attack  of  the  disease.  The  chief  difference 
between  an  antitoxic  serum  and  a  serum  which  is 
bactericidal  is,  that  an  antitoxin  acts  only  upon  a 
formed  poison,  while  a  bactericidal  serum  may  be 
protective,  preventing  an  infection.  The  antitoxin 
of  diphtheria  affords  the  best  example  of  an  antitoxic 
serum;  it  not  only  neutralizes  the  diphtheria  toxin, 
but  is  also  curative. 

Certain  bactericidal  sera  which  are  bacteriolytic 
(dissolving)  in  their  action  have  been  used  only  in  a 
limited  degree  in  the  diseases  of  man,  as  they  can  only 
be  artificially  cultivated  in  the  lower  animals  and 
have  not  always  proved  satisfactory,  because  of  the 
differences  in  species,  it  is  supposed.  The  blood- 
serum  from  animals  inoculated  with  typhoid  bacilli 
has  been  found  entirely  ineffective  when  used  for 
treating  the  disease  in  man ;  and  on  the  other  hand, 
the  use  of  the  bacterial  cells  by  vaccination  as  a 


IMMUNITY  61 

protection  against  typhoid  fever  has  attained  marked 
success. 

Phagocytosis.  —  In  1884  Metchnikoff1  established 
his  celebrated  theory  of  phagocytosis  as  an  explana- 
tion of  immunity.  Metchnikoff  believes  that  the 
wandering  cells  of  the  animal  organism — leucocytes 
— possess  the  power  of  digesting  or  rendering  inert  the 
bacteria  which  they  encounter  in  the  tissues;  and 
that  the  susceptibility  to  or  immunity  from  infection 
in  an  individual  is  decided  by  a  conflict  between  the 
invading  bacteria  on  one  side  and  the  leucocytes 
and  tissues  on  the  other,  the  outcome  depending  upon 
the  vigor  of  the  invaders  or  upon  the  provisions  for 
defense  set  up  by  the  leucocytes  and  tissues. 

When  the  vigor  of  the  body  cells  is  sufficient  to 
destroy  the  bacteria,  the  tissues  are  victorious,  but 
when  the  toxins  produced  by  the  bacteria  are  strong 
enough  to  arrest  the  activity  of  the  phagocytes,  an 
infection  follows. 

"...  the  migration  of  the  phagocytes  through 
the  vessel  wall  into  the  cavities  and  tissues  is  one 
of  the  principal  means  of  defense  possessed  by  an 
animal.  As  soon  as  the  infective  agents  have  pene- 
trated the  body,  a  whole  army  of  white  corpuscles 
(leucocytes)  proceeds  toward  the  menaced  spot, 

1  The  successor  of  Pasteur  in  the  Pasteur  Institute,  Paris. 


62  BACTERIOLOGY   FOR   NURSES 

there  entering  into  a  struggle  with  the  micro6rgan« 
isms."  (Metchnikoff,  1905.) 

Opsonins.  —  An  immense  amount  of  research  fol- 
lowed Metchnikoff's  discoveries,  one  of  the  great 
problems  being  to  find  the  reason  why  the  leucocytes 
do  not  always  attack  the  bacteria  and  prevent  infec- 
tion. Among  the  investigators  was  Sir  A.  E.  Wright 
of  England,  who,  with  others,  discovered  that  the 
blood-serum  contains  substances  which  are  necessary 
to  prepare  the  bacteria  for  the  leucocytes;  these 
substances  he  called  opsonins.  Opsonins  are  in  the 
blood  of  normal  animals,  but  are  greatly  increased 
by  immunization  and  differ  for  different  bacteria. 
The  process  whereby  the  opsonins  change  the  bac- 
teria and  render  them  liable  to  phagocytosis  is  not 
perfectly  understood. 

The  opsonic  index  is  the  mode  of  expressing  the 
relative  amount  of  opsonins  contained  in  the  blood- 
serum  in  comparison  to  the  normal. 

The  technique  of  this  work  is  extremely  compli- 
cated and  delicate. 

The  opsonic  method  of  treatment  aims  to  main- 
tain the  opsonic  index  at  a  high  level,  which  insures 
the  phagocytic  power  of  the  blood. 

"  Wright  and  Douglas  and  their  followers  have  found  it 
possible  to  artificially  increase  the  production  of  opsonins 


IMMUNITY  63 

in  the  blood  by  subcutaneously  injecting  into  the  patient 
a  carefully  measured  quantity  of  vaccine  (sterile  bac- 
teria). The  increased  phagocytosis  which  results  is  not 
due  to  any  direct  stimulation  of  the  leucocytes.  The 
newly  formed  opsonins  are  in  the  blood-serum  and  act  in 
some  unknown  way  on  the  bacteria,  so  changing  them 
that  the  white  blood  corpuscles,  or  scavengers  of  the  body, 
greedily  eat  them  up.  Careful  experiments  have  shown 
that  leucocytes  washed  free  of  serum  and  brought  into 
contact  with  an  emulsion  of  bacteria  show  no  phagocytic 
action,  while  if  they  are  brought  into  contact  with  the 
same  organisms  which  have  been  previously  bathed  in 
blood-serum  and  the  serum  then  carefully  washed  off,  the 
microbes  are  rapidly  engulfed  by  the  leucocytes. 

"A  personal  vaccine  is  prepared,  when  possible,  by  iso- 
lating the  organism  from  the  infected  individual,  but  as 
the  preparation  of  the  vaccine  requires  several  days  after 
the  organism  has  been  isolated,  the  first  dose  is  usually 
given  from  the  "  stock  bottle."  Stock  bottles  of  vaccine 
made  from  pure  cultures  of  various  kinds  of  bacteria  are 
kept  in  an  opsonic  laboratory,  each  bottle  of  course  con- 
taining only  one  kind  of  bacteria,  e.g.  staphylococcus. 
Since  it  requires  nearly  three  months  to  cultivate  the 
tubercle  bacillus  on  artificial  media,  it  is  plainly  evident 
that  it  is  impracticable  to  treat  tuberculous  patients  with 
personal  vaccines. 

"  The  normal  opsonic  index  is  1.0,  that  is,  there  is  in  the 
blood  of  normal  individuals  practically  an  equal  measure 
of  opsonins.  The  object  of  opsonic  therapy  is  to  raise 
and  maintain  the  opsonic  index  as  high  as  possible  above 


64  BACTERIOLOGY    FOR   NURSES 

normal,  for  as  long  a  period  as  possible,  thus  constantly 
preparing  multiplying  bacteria  as  palatable  food  for  the 
leucocytes,  until  the  infected  individual  has  become  im- 
munized against  the  infecting  organism. 

"  The  blood  is  examined  on  the  first  two  or  three  days  to 
see  whether  or  not  there  be  a  negative  phase  and  to  deter- 
mine the  maximal  rise  of  the  opsonic  index.  The  negative 
phase  consists  in  the  index  falling  lower  than  it  was  when 
the  vaccine  was  given,  and  has  occurred  but  rarely  in  our 
experience.  On  the  sixth  or  seventh  day  the  index  is 
again  determined,  and  as  soon  as  it  falls  to  one  or  below, 
another  injection  is  given.  Although  there  are  many 
chances  for  error  in  the  technique,  we  sincerely  feel  that 
the  opsonic  index  is  a  valuable  guide  in  regulating  the 
time  and  size  of  the  dosage,  and  should  be  carefully  fol- 
lowed until  we  find  a  better  guide."  (Vail  and  Lincoln.) 

Ehrlich's 1  "receptor  theory"  is  an  explanation  of  the  origin 
and  action  of  antitoxins  and  bactericidal  substances  in 
the  blood  of  the  immune.  The  subject  is  too  profound 
and  complex  to  be  embodied  ?n  a  book  of  this  character. 

In  acquired  immunity  the  blood-serum  sometimes 
acquires  the  property  of  agglutinating  the  bacteria, 
causing  the  infection.  This  agglutination  or  clump- 
ing is  brought  about  by  the  presence  in  the  blood- 
serum  of  an  anti-body  that  has  the  property  of 
bringing  about  the  clumping  of  the  bacteria  and 

1  Paul  Ehrlich,  Director  of  the  Royal  Prussian  Institute  for 
Experimental  Therapy.  Studies  in  Immunity. 


IMMUNITY  65 

causes  the  cessation  of  the  motility  of  motile  bac- 
teria. This  form  of  anti-body  is  known  as  "aggluti- 
nin."  The  Widal  test  as  a  means  of  diagnosis  of 
typhoid  fever  is  based  upon  this  agglutination  of 
bacteria  by  blood-serum.  A  drop  of  blood  from 
the  patient  is  added  to  a  specially  prepared  culture 
of  typhoid  bacilli;  if  the  bacilli  become  motionless 
and  soon  clump  (agglutinate)  in  irregular  masses, 
the  patient  is  doubtless  infected  with  the  bacillus 
of  typhoid.  Other  species  of  bacteria  are  also 
agglutinated  by  their  own  anti-sera.  It  is  not 
thought  that  agglutinins  are  bactericidal. 

"  Of  the  hypotheses 1  advanced  in  explanation  of 
acquired  immunity,  the  one  worthy  of  greatest  con- 
fidence is  that  which  assumes  immunity  to  be  due  to 
reactive  changes  on  the  part  of  the  tissues  that  result 
in  the  formation  in  these  tissues  of  antitoxic  and 
other  anti-bodies  which  circulate  free  in  the  blood 
and  in  a  variety  of  ways  serve  to  protect  the  tissues 
from  the  harmful  effect  of  extraneous  intoxicants 
and  irritants,  in  some  cases  acting  principally  as 
antidotes  to  a  toxin,  in  others  exhibiting  more  the 
germicidal  (bacteriolytic)  than  the  antitoxic  prop- 
erty." 

1  Abbott,  Principles  of  Bacteriology. 


CHAPTER  VII 

INFLAMMATION,  SUPPURATION,  PNEUMONIA,  EPIDEMIC 
CEREBRO-SPINAL    MENINGITIS 

THE  microorganisms  which  produce  inflammation 
and  suppuration,  known  as  pyogenic  or  pus-forming 
bacteria,  are  of  especial  interest  to  the  nurse,  her 
daily  routine  being  an  almost  constant  combat 
with  these  unseen  germs,  toward  whose  activities 
especially  is  directed  the  complex  surgical  technique 
which  prevails  in  every  department  of  the  hospital. 

Inflammation  and  Suppuration  may  be  due  to 
several  organisms,  no  one  organism  being  the  cause ; 
and  two  or  more  may  be  present,  while  the  same 
organism  may  produce  entirely  different  results  under 
varying  conditions,  as  in  different  individuals,  or  in 
the  same  person  when  resistance  is  lowered,  or  when 
the  virulence  of  the  bacteria  is  increased  or  lessened 
from  any  cause;  which  accounts  for  the  remarkable 
diversity  in  the  character  of  infections.  For  ex- 
ample, a  minute  pin  prick  may  carry  virulent  organ- 
isms into  the  blood  of  a  person  whose  resistance  is 


INFLAMMATION,    SUPPURATION  67 

weak,  the  result  being  a  severe  general  infection; 
while  in  another  case  an  extensive  wound  which 
seemed  to  have  had  every  condition  favorable  to  a 
grave  infection,  healed  by  " first  intention"  or  with 
no  sign  of  inflammation  or  suppuration. 

In  suppuration  there  is  a  gathering  of  the  leucocytes 
to  the  point  of  infection,  followed  by  a  liquefaction 
of  the  tissue  with  necrosis  (death)  of  the  cells,  the 
result  being  a  creamy  fluid  which  we  know  as  pus. 
There  may  be  inflammation  without  suppuration. 

In  septiccernia  the  organisms  develop  in  the  blood, 
and  there  may  be  no  local  point  of  infection,  but 
symptoms  of  profound  general  poisoning. 

In  pyoBtnia  abscesses  occur  in  all  parts  of  the  body, 
externally  as  well  as  in  the  internal  organs. 

The  bacteria  commonly  found  in  boils;  carbuncles, 
abscesses,  and  many  other  infections  be- 
long to  the  group  called  staphylococci,  of       .%.  \ 
which  there  are  two  types :  staphylococcus     ": "    '& 
[pyogenes]  albus,  and  staphylococcus  (pyo- 
genes) aureus,  the  latter  distinguished  by  its  produc' 
tion  of  a  bright  yellow  pigment. 

The  cells  of  staphylococcus  aureus  are  arranged  in 
irregular  groups  not  unlike  clusters  of  grapes,  and 
are  said  to  be  the  most  resistant  to  drying,  heat,  and 
chemicals  of  any  of  the  non-spore-bearing  bacteria. 


68  BACTERIOLOGY   FOR   NURSES 

The  staphylococcus  aureus  is  found  almost  con- 
stantly upon  the  skin,  and  is  supposed  to  have  at 
times  the  power  to  penetrate  the  skin  through  the 
sweat-ducts,  several  diseases  of  the  skin  being 
attributed  to  its  activities;  while  suppurative  in- 
flammations in  all  parts  of  the  body  are  usually 
found  to  contain  the  organisms. 

Infections  from  staphylococci  are  not  unknown 
among  domestic  animals ;  horses,  cattle,  and  rabbits 
being  more  susceptible  than  other  animals. 

The  streptococcus  pyogenes  is  a  coccus  slightly 
larger  than  the  staphylococcus,  which  grows  in 
chains  of  varying  length,  it  being  thought  at  one 
time  that  the  length  of  the  chain 
/  x  S  signified  the  degree  of  virulence 
°  f  of  the  germs,  but  this  has  not 

v  been  proven  by  experiment. 

There  are  many  so-called  strains 
of  the  streptococcus,  and  probably  no  other  disease- 
producing  organism  causes  as  many  and  varied 
disturbances  in  man,  being  not  only  the  primary 
cause  of  many  infections,  but  frequently  found  in 
mixed  and  in  secondary  infections.  Erysipelas, 
puerperal  fever,  suppurative  conditions  of  all  of  the 
organs,  pneumonia,  ulcerative  endocarditis  (an 
affection  of  the  valves  of  the  heart),  otitis  media  (in- 


INFLAMMATION,    SUPPURATION  69 

flammation  of  the  middle  ear),  and  rheumatic  fever 
are  all  attributed  to  streptococcus  pyogenes. 

The  mucous  membranes  frequently  harbor  strepto- 
cocci, the  tonsils  being  a  favorite  resting  place. 
Diphtheria  is  nearly  always  accompanied  by  an 
abundance  of  streptococci,  which  were  at  one  time 
thought  to  be  the  cause  of  the  disease.  Streptococcic 
infections  following,  or  secondary  to,  other  infections 
occur  often  in  tuberculosis,  smallpox,  and  scarlet 
fever;  and  septicaemia,  due  to  streptococci,  occurs 
in  many  diseases. 

In  the  lower  animals,  horses,  cattle,  rabbits,  and 
mice  are  all  .susceptible  to  infections  from  strepto- 
cocci. 

Immunity  following  streptococcic  infection  is  of 
short  duration.  Efforts  have  been  made  to  utilize 
the  serum  of  immunized  animals  both  for  the  protec- 
tion and  cure  of  streptococcic  infections  in  man,  but 
the  results  have  been  uneven  and  upon  the  whole  not 
very  satisfactory. 

To  the  two  organisms  staphylococci  and  strepto- 
cocci are  due  most  of  the  innumerable  train  of  infec- 
tions liable  to  occur  in  hospitals,  which  are  a  con- 
stant source  of  anxiety  to  doctors  and  nurses.  The 
everyday  routine  of  a  hospital  ward  affords  end- 
less opportunities  for  infection  to  be  carried  from 


70  BACTERIOLOGY    FOR   NURSES 

one  patient  to  another,  and  the  knowledge  that 
staphylococci  and  streptococci  are  commonly  found 
upon  the  skin,  in  the  mouth,  and  in  the  nasal 
passages  should  be  sufficient  to  prompt  the 
greatest  care  in  taking  temperatures  by  mouth, 
in  giving  hypodermic  injections,  in  the  use  of 
catheters,  rectal  tubes,  douche  points,  and  medicine 


The  nurse's  care  of  her  own  hands  is  of  vital  im- 
portance to  herself  as  well  as  to  her  patients ;  in 
caring  for  a  patient  she  has  no  way  of  knowing  what 
bacteria  his  body  may  harbor,  which  may  be  a  source 
of  danger  to  the  next  patient  as  well  as  to  herself, 
and  for  this  reason  she  cannot  be  too  careful  about 
scrubbing  (not  simply  washing  or  rinsing)  her  hands 
after  every  bath,  enema,  douche,  catheterization, 
etc.,  as  well  as  giving  them  scrubbing  and  disinfec- 
tion before. 

At  first  sight  the  elaborate  technicalities  of  oper- 
ating-room work  seems  a  hopeless  and  inextricable 
tangle  to  the  beginner ;  but  gradually  the  reasons  and 
results  begin  to  define  themselves,  and  slowly  the 
whole  technique  for  the  prevention  of  infection  unfolds 
itself,  and  the  conscience  which  permits  no  lapses  or 
gaps  in  the  chain  which  binds  the  whole  together 
begins  to  develop,  until  at  last  out  of  the  laboratory 


PNEUMONIA 


and  operating-room  drill  the  nurse  awakens  to  an 
entirely  new  conception  of  her  duties  and  of  all  her 
surroundings. 


PNEUMONIA 

The  acute  inflammation  of  the  lungs  known  as 
pneumonia  is  generally  due  to  a  micrococcus  known 
by  several  names :  streptococcus  pneumonia,  or  diplo- 
coccus  (in  pairs)  pneumonice,  or  pneumococcus,  or 
Frdnkel' s  diplococcus 
pneumonice,  after  its 
discoverer;  the  term 
pneumococcus  being 
used  more  commonly  jj|  /  '  || 

than      any      other,    L  ''.'!'",'"*'"'         <  •'          : 

probably  on  account  ';'•"»* 

of  its  brevity.  [^:^f-. 

The  pneumococcus  ^ ,  >; 

often  occurs  in  pairs  JiP^ 

(diploCOCCi)  Or  Short  FIG.  14.  — Film  preparation  of  pneumonic 
sputum,  showing  numerous  pneumococci 

Chains.  USUally  Show-  (Frankel's)  with  unstained  capsules. 
XlOOO. 

ing  a  capsule  or  clear 

zone  surrounding  the  cell  and  bearing  a  marked 

resemblance  to  streptococcus  pyogenes. 

Pneumonia  manifests  several  different  types  and  is 


72  BACTERIOLOGY   FOE  NURSES 

not  always  due  to  an  invasion  of  pneumococci, 
neither  does  the  pneumococcus  always  produce  the 
same  results,  the  variations  no  doubt  being  largely 
due  to  the  condition  of  the  individuals.  It  was 
formerly  thought  that  exposure  to  cold  was  the  sole 
cause  of  pneumonia,  and  it  is  true  that  such  exposure 
by  lowering  resistance  opens  the  way  for  an  invasion 
of  bacteria,  while  other  factors,  such  as  dissipation, 
loss  of  sleep,  lack  of  food,  and  prostration  due  toother 
diseases,  as  typhoid  fever,  scarlet  fever,  and  measles, 
may  all  be  contributory  to  an  attack  of  pneumonia. 

There  are  three  types  of  pneumonia :  lobar  (acute 
croupous),  broncho-pneumonia,  or  lobular  pneumonia, 
and  capillary  bronchitis. 

Lobar  pneumonia  is  said  to  be  due  almost  entirely 
to  the  pneumococcus,  which  is  found  in  the  blood, 
while  lobular  pneumonia  and  capillary  bronchitis 
are  sometimes  due  to  other  organisms,  as  staphylo- 
coccus,  or  streptococcus,  or  B.  diphtheria,  or  B. 
influenza,  or  B.  typhosus.  Pneumococci  are  not  only 
the  cause  of  lobar  and  lobular  pneumonia,  but 
many  other  inflammations  and  suppurative  condi- 
tions, as  inflammation  of  the  middle  ear,  of  the 
meninges  (meningitis),  of  the  pleura  (pleurisy),  and, 
in  fact,  infections  due  to  the  pneumococcus  have 
been  found  in  nearly  every  organ  of  the  body. 


PNEUMONIA  73 

The  fact  that  the  pneumococcus  may  be  found  in 
the  mouth  or  nasal  passages  of  nearly  all  healthy 
persons  renders  it  an  organism  to  be  feared;  al- 
though the  mode  of  dissemination  is  still  a  point  in 
doubt,  and  all  authorities  do  not  entirely  agree  as  to 
the  dangers  of  infection,  although  many  so-called 
epidemics  have  occurred,  yet  there  is  enough  evidence 
to  warrant  careful  measures  in  the  nursing  of  pneu- 
monia patients  to  protect  others  from  the  possibility 
of  contagion. 

All  cloths  used  for  handkerchiefs  and  mouth 
sponges  should  be  burned  immediately;  nightgowns 
and  bedding  should  be  protected  from  mouth  and 
nasal  discharges  and  should  be  frequently  changed  and 
disinfected;  the  hands  of  both  the  patient  and  the 
nurse  should  have  the  closest  care;  no  delirious 
pneumonia  patient  can  properly  use  his  handkerchief 
nor  sputum  cup  and  will  soil  his  hands  constantly 
with  discharges  from  his  mouth  and  nose,  thus  re- 
quiring the  most  scrupulous  care. 

Discharges  lodging  upon  the  floor,  or  bedside  table, 
or  nurse's  uniform  should  be  wiped  away  at  once  with 
cloths  wet  in  a  solution  of  bichloride  of  mercury 
1 : 1000.  No  rugs  or  carpets  should  be  allowed  in  the 
sick  room  of  a  pneumonia  patient. 

Immunity  following  pneumonia  is  of  very  short 


74  BACTERIOLOGY    FOR    NURSES 

duration,  a  second  attack  often  following  the  first  at 
a  short  interval. 

Some  of  the  lower  animals  are  susceptible  to 
infection  from  the  pneumococcus,  rabbits  and  mice 
particularly,  guinea  pigs  being  less  so,  and  dogs  very 
resistant. 

One  of  Pasteur's  early  experiments  was  the  in- 
jection of  human  saliva  into  rabbits,  causing  a  rapid, 
fatal  general  infection  which  he  called  sputum  septicce- 
mia,  and  which  is  now  known  to  be  due  to  the 
pneumococcus. 


EPIDEMIC    CEREBRO-SPINAL  MENINGITIS 

An  inflammation  of  the  meninges,  or  membranes 
covering  the  brain  and  spinal  cord,  is  known  as  men- 
ingitis and  may  be  due  to  one  of  several  different  or- 
ganisms, which  may  be  primary  infections  or  follow 
some  previous  infection  occurring  in  another  part  of 
the  body. 

Meningitis  may  be  caused  by  streptococcus  pyogenes, 
by  pneumococcus,  or  by  bacillus  tuberculosis,  but  these 
cases  are  never  epidemic,  occurring  only  in  scattered 
instances. 

Epidemic  cerebro-spinal  meningitis  is  an  acute  infec- 
tious disease  due  to  an  organism  known  as  menin* 


EPIDEMIC    CEREBRO-SPINAL    MENINGITIS  75 

gococcus,  a  small  coccus,  occurring  in  pairs,  which  is 
sometimes  difficult  to  cultivate  in  artificial  media. 

The  disease  is  most  common  in  children  and  young 
adults,  seldom  appearing  after  thirty-five  years  of  age. 

The  death  rate  is  very  high,  averaging  70  per  cent, 
but  meningitis  due  to  other  bacteria  is  fatal  in  nearly 
all  cases. 

The  portal  of  entry  and  mode  of  dissemination  in 
epidemic  cerebro-spinal  meningitis  are  still  doubtful 
subjects.  It  is  thought  that  the  nasal  cavity  and  the 
middle  ear  are  the  avenues  of  entrance. 

The  fact  that  the  meningococcus  has  a  very  slight 
resistance  to  drying  would  seem  to  indicate  that 
the  disease  is  spread  by  germ  carriers,  whether 
convalescents,  actual  patients,  or  healthy  persons. 
Contact  with  fresh  infective  material,  as  might  oc- 
cur upon  handkerchiefs,  towels,  dishes,  thermom- 
eters, bedding  or  hands,  is  also  an  avenue  for  the 
spread  of  infection. 

An  anti-meningitis  serum  obtained  by  the  immu- 
nization of  horses  has  been  used  with  very  good 
results.  In  one  epidemic  of  meningitis  the  Flexner- 
Jobling  serum  was  used  in  forty-seven  cases,  with 
thirty-four  recoveries  and  thirteen  deaths,  a  very 
marked  decrease  in  the  average  death  rate  of  70  per 
cent. 


CHAPTER  VIII 


THE    VENEREAL   DISEASES 
GONORRHOEA,  SYPHILIS  * 

Gonorrhoea  is  an  inflammation  of  the  urethra  due 
to  a  coccus  known  as  the  gonococcus  of  Neisser,  who 
discovered  it,  or  as  micrococcus  gonorrhoea,  and 

-  is  said  to  be  one  of 
the  most  widely  dis- 
tributed  diseases   in 
|     the    world,    German 
:  A    statistics    estimating 
Jj    that  48.5  per  cent  or 
If    more    of    the    male 
f     population   are   thus 
afflicted. 

In  appearance  the 
gonococcus    bears    a 
striking  resemblance 
occurring    in    pairs    with 


FIG.  15.  —  Film  of  pus  of  gonorrhoea 
showing  gonococci. 


to   the    meningococcus, 


1  Read :  Hygiene  of  Transmissible  Diseases.     Abbott,  p.  166. 
Also  chapters  upon  gonorrhoea  and  syphilis,  to  be  found  in  all 
standard  works  on  the  practice  of  medicine. 
76 


THE   VENEREAL   DISEASES  77 

slightly  flattened  sides,  and  like  the  meningococcus 
it  is  found  in  the  pus  cells;  but  the  two  germs 
are  not  often  confused,  as  they  are  almost  never 
found  in  the  same  tissues.  Special  culture  media 
are  required  for  the  artificial  growth  of  the  gono- 
coccus,  which  is  sensitive  to  drying  and  variations  of 
temperature. 

While  gonorrhoea  is  primarily  an  inflammation  of 
the  urethra,  the  infection  is  by  no  means  localized, 
and  may  cause  far-reaching  and  disastrous  results, 
particularly  in  women.  Stricture  of  the  urethra 
is  the  most  common  result  in  men;  but  in  women 
the  uterus,  Fallopian  tubes,  and  the  peritoneum 
are  frequently  infected,  resulting  in  a  train  of  serious 
disorders  which  necessitate  extensive  surgical  opera- 
tions, and  in  nearly,  if  not  quite  all  cases  cause  sterility. 

Gonorrhoea  ophthalmia,  which  is  the  cause  of  10 
per  cent  of  all  cases  of  blindness,  occurs  in  the  new- 
born from  infection  from  the  mother,  and  in  later 
cases  the  infection  may  be  carried  to  the  eyes  by 
hands,  handkerchiefs,  towels,  or  any  object  which 
may  have  been  handled  or  touched  by  a  person 
suffering  from  gonorrhoea. 

The  gono  coccus  may  gain  entrance  to  the  blood 
and  be  carried  in  the  circulation  to  all  parts  of  the 
body;  the  synovial  membranes  covering  the  joints 


78  BACTERIOLOGY   FOR   NURSES 

are  a  favorite  resting  place,  resulting  in  arthritis,  or 
gonorrhceal  rheumatism. 

"A  peculiarly  dangerous  feature  of  gonococcus 
infection  is  the  long  period  during  which  an  infected 
man  or  woman  may  be  capable  of  infecting  others. 
Gonococci  may  persist  in  the  genito-urinary  secre- 
tions for  years  after  apparently  complete  recovery 
has  taken  place.  By  this  means  serious  inflamma- 
tions of  the  genital  tract  are  produced  in  thousands 
of  innocent  wives  by  their  previously  infected  hus- 
bands." (Jordan.) 

Epidemics  of  vulvovaginitis  in  little  girls  are  not 
an  uncommon  occurrence  in  schools  and  in  institu- 
tions, and  present  almost  insurmountable  difficulty 
in  stamping  them  out.  Such  infections  usually  origi- 
nate in  unclean,  overcrowded  tenements  where  chil- 
dren occupy  the  same  beds  with  adults,  and  where 
baths  and  clean  clothing  are  infrequent,  and  are 
then  carried  into  schools  and  disseminated  by  con- 
tact with  clothing  and  the  water-closet  seats.  If 
introduced  into  children's  hospitals  or  wards,  it 
may  be  carried  by  bath  tubs,  towels,  wash  cloths, 
dishes,  diapers,  bed  and  body  linen,  and  closet 
seats. 

The  most  lamentable  result  of  these  epidemics  of 
vaginitis  among  the  little  girls  is  the  fact  that  the 


THE   VENEREAL   DISEASES  79 

consequences  to  the  reproductive  organs  are  quite 
as  grave  as  when  produced  in  any  other  manner. 

No  other  epidemic  occurring  in  the  hospital  is  so 
difficult  to  control  as  the  cases  of  vulvovaginitis  in 
little  girls.  These  children  should  be  isolated,  and 
it  seems  to  be  the  consensus  of  opinion  that  all  such 
patients  should  wear  a  vulvar  pad  made  of  absorbent 
cotton  held  in  place  by  a  T  bandage,  both  being 
changed  at  least  every  six  hours  and  burned  im- 
mediately upon  removal,  as  experiments  have  proved 
that  the  ordinary  laundry  process  supplemented 
by  sterilization  will  not  render  diapers  safe  to  use 
upon  a  healthy  child. 

So  grave  and  so  persistent  are  these  epidemics  in 
hospitals  and  other  public  institutions  where  large 
numbers  of  children  are  congregated  that  some  hospi- 
tals make  it  an  inflexible  rule  to  burn  all  diapers  from 
non-infected  as  well  as  infected  children,  that  there 
may  be  no  possible  danger  from  that  source. 

The  use  of  common  bath  tubs  and  water-closet 
seats  are  two  very  easy  methods  of  carrying  infection 
unless  both  are  scalded  and  disinfected  with  chemi- 
cals several  times  daily. 

It  often  happens  that  wards  where  such  epidemics 
have  occurred  are  emptied  of  patients,  fumigated  with 
formalin,  and  beds,  furniture,  floors,  walls,  and  wood- 


80  BACTERIOLOGY   FOR   NURSES 

work  painted  or  varnished,  mattresses  and  pillows 
discarded,  bed  and  body  clothing  sterilized,  all  toys 
and  books  destroyed,  and  the  ward  may  stand  empty 
for  a  month,  open  to  the  sun  and  air;  and  when 
opened,  with  only  new  patients  and  new  nurses,  a 
fresh  epidemic  will  occur  within  a  fortnight,  and 
worse  than  all,  this  process  may  have  to  be  repeated 
three  or  four  times,  covering  a  period  of  months, 
while  every  doctor  and  nurse  in  the  hospital  is  exer- 
cising every  possible  precaution  which  intelligence 
and  ingenuity  can  contrive,  to  control  it. 

A  gonococcus  vaccine  has  been  employed  for  gono- 
rrhceal  rheumatism,  with  favorable  results. 

The  lower  animals  are  not  susceptible  to  infection 
from  the  gonococcus,  although  the  injection  of  the 
poisonous  products  contained  in  cultures  have  caused 
death  in  some  animals.  The  gonococci  do  not  in- 
vade the  tissues  of  the  lower  animals. 

SYPHILIS 

Syphilis  is  a  chronic  infectious  disease  character- 
ized by  certain  lesions  of  which  the  chancre,  the 
gumma,  and  the  mucous  patch  are  the  most  destruc- 
tive. 

Syphilis  is  liable  or  may  infect  any  or  every  tissue 
of  the  body.  Efforts  to  identify  the  microorganism 


THE   VENEREAL   DISEASES  81 

which  causes  syphilis  have  extended  over  a  long 
period,  and  not  until  very  recently  has  any  definite 
conclusion  been  agreed  upon.  Through  a  series  of 
experiments  by  Schaudinn  and  Hoffman,  which  were 
confirmed  by  Metchnikoff  and  others,  it  has  been 
decided  that  syphilis  is  due  to  a  spirillum  known  as 
Treponema  pallidum,  the  reasons 
for  the  long  delay  in  arriving 
at  a  decision  being  the  fact  that 
the  organism  is  exceedingly 
difficult  to  stain,  and,  without 
staining,  it  is  almost  impossible  FIG.  ie.  — 

pallidum. 

to  see  it. 

For  many  years  all  efforts  to  cultivate  Treponema 
pallidum  upon  an  artificial  medium  were  unsuccess- 
ful, although  monkeys  had  been  inoculated  and  from 
the  lesions  other  monkeys  were  successfully  inocu- 
lated, which  seemed  to  be  conclusive  evidence  that 
Treponema  pallidum  undoubtedly  caused  syphilis. 
Schereschewsky,  a  German  bacteriologist,  was  the 
first  to  bring  about  the  growth  of  Treponema  pal- 
lidum on  artificial  media  (1909). 

Syphilis  is  transmitted  by  sexual  congress,  may 
be  transmitted  by  a  diseased  parent,  or  may  be 
acquired  by  inoculation  through  an  abrasion  of  the 
skin  or  mucous  membranes. 


82  BACTERIOLOGY   FOR   NURSES 

Syphilis  may  be  transmitted  by  the  father,  the 
mother  being  perfectly  healthy,  or  it  may  be  trans- 
mitted by  a  syphilitic  mother.  Syphilis  in  a  parent 
may  have  apparently  entirely  disappeared,  and  yet 
children  born  subsequently  will  or  may  show  evi- 
dences of  the  disease.  A  curious  phenomenon  re- 
garding the  hereditary  transmission  of  syphilis  is 
that  shown  in  Colic's  Law,  viz.  "  a  child  born  of  a 
mother  who  is  without  obvious  venereal  symptoms, 
and  which  without  being  exposed  to  any  infection 
subsequent  to  its  birth  shows  the  disease  when  a 
few  weeks  old,  —  such  a  child  will  infect  the  most 
healthy  nurse,  whether  she  suckle  it  or  merely  handle 
and  dress  it ;  and  yet  this  child  will  not  infect  its 
own  mother,  even  though  she  suckle  it  while  it  has 
venereal  ulcers  of  the  lips  and  tongue." 

The  infection  upon  the  lips  may  be  contracted 
by  kissing  a  syphilitic  person  or  using  infected 
dishes ;  a  wet  nurse  may  infect  a  healthy  child  and 
vice  versa.  Surgical  and  dental  instruments  which 
are  not  properly  cleaned  nor  sterilized  are  grave 
sources  of  danger,  and  doctors  and  nurses  may  easily 
become  inoculated  while  dressing  syphilitic  ulcers  or 
other  lesions  upon  their  patients. 

The  whole  subject  of  venereal  diseases,  and 
especially  of  their  transmission,  is  of  vital  impor- 


THE    VENEREAL   DISEASES  83 

tance  to  nurses,  who  should  early  inform  themselves 
of  the  far-reaching  consequences  of  venereal  infec- 
tions. The  subject  heretofore  has  been  considered 
almost  wholly  (outside  of  the  medical  profession) 
from  the  moral  standpoint,  and  it  is  very  evident  that 
the  world  at  large  —  women  in  particular  —  should 
have  a  perfectly  clear  idea  of  its  physical  aspects 
in  order  to  defend  themselves  and  their  children 
from  the  ravages  of  these  loathsome  infections. 

One  of  the  special  points  of  the  subject  to  remem- 
ber is  the  fact  that  the  infections  of  both  gonorrhea 
and  syphilis  are  chronic,  that  is,  we  may  truthfully 
say  that  the  patients  almost  never  recover;  the 
acute  symptoms  will  pass  away  and  there  is  seeming 
recovery,  but  the  germs  are  only  latent,  and  children 
must  bear  the  burden  of  their  hideous  manifes- 
tations. 

Transmission  of  gonorrhoea  and  syphilis  is  by 
inoculation  —  the  germs  must  gain  access  to  the 
blood  —  which  can  occur  only  by  contact.  Sexual 
congress  and  heredity  will  account  for  a  large 
majority  of  cases,  but  there  are  enough  instances  of 
doctors  and  nurses  contracting  the  diseases  in  the 
pursuit  of  their  professional  duties  to  warrant  the 
exercise  of  the  most  scrupulous  care  of  all  utensils, 
clothing,  and  their  own  hands  while  working  over 


84  BACTERIOLOGY   FOR   NURSES 

syphilitic  patients  or  those  suffering  from  gonor- 
rhoea. 

The  use  of  rubber  gloves  is  one  of  the  best  means 
of  protecting  every  one  concerned :  no  process  can 
be  devised  for  disinfecting  the  hands  which  can 
equal  the  use  of  rubber  gloves,  which  should  be 
boiled  both  before  and  after  using  and  should  never 
be  used  for  other  patients. 


CHAPTER  IX 

TUBERCULOSIS.      LEPROSY 

TUBERCULOSIS  is  the  most  widespread  disease 
known.  In  the  United  States  it  was  estimated  that 
one  ninth  of  all  deaths  which  occurred  in  1900  were 
due  to  tuberculosis,  and  that  the  cost  to  the  country 
reached  nearly  to  $200,000,000. 

Historical.  —During  1870-1880  different  investiga- 
tors proved  that  tuberculosis  was  an  infective  disease 
but  did  not  discover  the  organism  which  caused  it. 

"  The  announcement  of  the  discovery  of  the  tubercle 
bacillus  was  made  by  Koch  in  March,  1882,  and  a  full 
account  of  his  researches  appeared  in  1884  (Mitth.  a.  d.  K. 
Gsndhtsamte.,  Berlin).  Koch's  work  on  this  subject 
will  remain  as  a  classical  masterpiece  of  bacteriological 
research,  both  on  account  of  the  great  difficulties  which  he 
successfully  overcame  and  the  completeness  with  which 
he  demonstrated  the  relations  of  the  organism  to  the  dis- 
ease. The  two  chief  difficulties  were,  first,  the  demon- 
stration of  the  bacilli  in  the  tissues,  and,  secondly,  the 
cultivation  of  the  organism  outside  the  body.  For, 
with  regard  to  the  first,  the  tubercle  bacillus  cannot  be 
85 


86  BACTERIOLOGY   FOR   NURSES 

demonstrated  by  a  simple  watery  solution  of  a  basic 
aniline  dye,  and  it  was  only  after  prolonged  staining  for 
twenty-four  hours,  with  a  solution  of  methylene-blue 
with  caustic  potash  added,  that  he  was  able  to  reveal  the 
presence  of  the  organism.  Then,  in  the  second  place, 
all  attempts  to  cultivate  it  on  the  ordinary  media  failed, 
and  he  only  succeeded  in  obtaining  growth  on  solidified 
blood-serum,  the  method  of  preparing  which  he  himself 
devised,  inoculations  being  made  on  this  medium  from 
the  organs  of  animals  artificially  rendered  tubercular. 
The  fact  that  growth  did  not  appear  till  the  tenth  day  at 
the  earliest,  might  easily  have  led  to  the  hasty  conclusion 
that  no  growth  took  place.  All  difficulties  were,  however, 
successfully  overcome.  He  cultivated  the  organism  by 
the  above  method  from  a  great  variety  of  sources,  and  by 
a  large  series  of  inoculation  experiments  on  various  ani- 
mals, performed  by  different  methods,  he  conclusively 
proved  that  bacilli  from  these  different  sources  produced 
the  same  tubercular  lesions  and  were  really  of  the  same 
species.  His  work  was  the  means  of  showing  conclusively 
that  such  conditions  as  lupus,  "white  swelling"  of  joints, 
scrofulous  disease  of  glands,  etc.,  are  really  tubercular  in 
nature."  (Muir  and  Ritchie.) 

Koch's  discovery  is  considered  the  most  important 
single  discovery  in  the  history  of  medical  science. 

Tubercle  bacilli  are  minute  rods  from  2  ft  to  3.5  ft 
or  4  ft  in  length  and  about  0.5  ft  in  breadth,  occurring 
singly  or  in  small  groups,  and  surrounded  by  a  cap- 


TUBERCULOSIS.       LEPROSY 


87 


sular  substance.  The  tubercle  bacillus  is  non-motile, 
and  is  supposed  to  produce  no  spores,  although  some 
difference  of  opinion  upon  this  point  still  exists. 

Staining  and  Culti- 
vation. —  The  tubercle 
bacillus  stains  im- 
perfectly or  with  great 
difficulty,  and  when 
once  stained  resists 
all  efforts  to  decol- 
orize it  with  acids; 
it  is  known  with  a 

few  other  organisms  FIG.  17.—  Tubercle  batim. 

as  an  "acid-proof  bacillus."  This  characteristic  re- 
sistance to  staining  and  decolorization  constitutes  one 
of  the  chief  means  of  identifying  the  organism. 

The  cultivation  of  the  tubercle  bacillus  upon  arti- 
ficial media  is  very  slow  and  uncertain.  Koch  first 
succeeded  in  cultivating  it  upon  blood-serum,  which 
still  remains  the  most  satisfactory  medium.  When 
cultures  have  been  successfully  grown  it  is  less  diffi- 
cult to  transfer  them  to  other  substances  such  as 
potato,  carrot,  or  macaroni. 

No  growth  is  discernible  before  the  end  of  ten  days, 
which  probably  accounts  for  the  many  failures  of 
early  investigators.  Cultures  from  the  tissues  show 


88  BACTERIOLOGY  FOR   NURSES 

a  more  scanty  growth  than  sub-cultures,  but  are 
always  distinctly  characteristic,  appearing  as  dry 
masses  like  dry  meal  spread  over  the  medium  and  of 
dull  whitish  or  pale  drab  color,  sometimes  emitting  a 
peculiar  odor.  Growth  occurs  within  a  narrow  range 
of  temperature,  37°-38°  C.  (98.6°  F.-100.40  F.),which 
corresponds  to  the  normal  temperature  of  the  human 
body ;  but  by  a  series  of  sub-cultures,  growths  have 
been  observed  in  a  temperature  as  low  as  23°  C.  (73.4° 
F.) .  The  tubercle  bacillus  is  one  of  the  few  organisms 
which  grow  better  upon  a  slightly  acid  medium. 

Powers  of  Resistance.  —  The  resistance  of  the 
tubercle  bacillus  is  considerable,  as  it  retains  its 
vitality  outside  of  the  human  body  for  some  time, 
which  constitutes  the  chief  danger  in  the  transmission 
of  the  disease.  The  bacilli  in  dried  sputum  will  re- 
tain their  vitality  while  floating  in  the  air  for  several 
days,  and  if  lodged  in  a  cool  dark  place,  may  survive 
for  six  months.  They  are  highly  resistant  to  dry 
heat,  surviving  100°  C.  (212°  F.)  for  more  than  an 
hour,  but  will  be  killed  by  moist  heat  at  60°  C. 
(140°  F.)  in  twenty  minutes.  Freezing  does  not 
always  destroy  them,  but  exposure  to  sunlight  will 
kill  them  in  a  few  hours. 

Of  all  of  the  chemicals  used  for  germicidal  purposes 
carbolic  acid  and  its  preparations  have  been  found 


TUBERCULOSIS.       LEPROSY  89 

to  be  most  effectual  in  destroying  the  tubercle 
bacilli.  Lysol,  which  is  a  preparation  of  carbolic 
acid,  has  a  solvent  effect  upon  mucus,  besides  being 
an  excellent  germicide,  which  makes  it  preferable  to 
any  other  preparation  for  the  disinfection  of  sputum 
from  patients  suffering  from  phthisis. 

Tuberculous  Infection  in  Man.  —  The  tubercle 
bacillus  is  one  of  the  few  organisms  which  invades 
every  tissue  and  organ  of  the  human  body.  The 
lungs  are  the  most  common  seat  of  infection,  but  the 
larynx,  the  intestines  and  mesenteric  glands,  the 
glands  of  the  neck,  the  bones  and  joints,  the  urinary 
tract,  and  the  skin  are  frequently  infected. 

The  lesions  caused  by  the  tubercle  bacillus  are 
characteristic  nodules  or  tubercles  which  may  be 
plainly  seen  with  the  naked  eye  in  the  more  advanced 
stages  of  some  forms  of  the  disease.  The  general 
symptoms  are  wasting,  fever,  and  perspiration,  which 
are  due  to  the  toxic  products  of  the  bacilli,  and  in  pul- 
monary tuberculosis  (phthisis)  the  frequent  presence 
of  other  bacteria  may  cause  various  other  symptoms. 

Tuberculosis  in  the  Lower  Animals.  —  Tubercu- 
losis occurs  frequently  in  cattle  and  swine.  In  Eu- 
rope statistics  show  that  from  15  to  20  per  cent  of 
cattle  and  from  2  to  3  per  cent  of  swine  are  tubercu- 
lous. In  the  United  States  the  percentage  is  much 


90  BACTERIOLOGY    FOR    NURSES 

lower,  .134  per  cent  only  being  recorded;  some 
allowance  is,  however,  made  for  the  differences  in 
compiling  statistics.  The  appearance  of  the  tubercle 
bacillus  in  man  and  the  bovine  bacillus  is  somewhat 
different,  the  latter  being  shorter.  The  very  impor- 
tant question  as  to  man's  susceptibility  to  bovine 
tuberculosis  is  still  a  matter  of  controversy,  although 
enough  evidence  has  been  collected  to  prove  that  the 
bovine  bacillus  is  found  in  man.  Bovine  infection 
occurs  much  more  frequently  in  children  under 
five  years  of  age  than  in  adults,  which  is  supposed 
to  be  due  to  their  diet  consisting  largely  of  milk. 
Tuberculous  meat  is  less  dangerous  than  milk, 
because  cooking  will  destroy  the  bacilli. 

Tuberculosis  is  common  among  fowls,  turkeys, 
and  pigeons,  but  ducks  and  geese  are  exempt.  Fish 
also  are  affected  by  a  disease  due  to  an  organism 
which  resembles  the  tubercle  bacillus. 

Channels  of  Infection.  —  The  chief  avenue  of  in- 
fection is  the  respiratory  tract.  It  is  estimated 
that  a  patient  suffering  from  phthisis  may  expecto- 
rate over  500,000,000  bacilli  in  twenty-four  hours, 
and  even  with  the  most  scrupulous  care,  every  act  of 
coughing  or  sneezing  projects  large  numbers  into  the 
air,  where  they  may  be  inhaled  by  healthy  persons. 
The  action  of  sunlight  and  of  drying  kills  the  majority 


TUBERCULOSIS.       LEPROSY  91 

in  the  air,  but  many  will  find  favorable  lodging  places 
where  they  may  retain  their  vitality  for  weeks. 

Infection  through  the  alimentary  tract  is  usually 
ascribed  to  butter  or  milk  from  tuberculous  cows, 
but  tubercle  bacilli  could  easily  be  taken  with  food 
infected  by  handling,  or  from  common  drinking  cups, 
or  from  dishes  or  food  infected  by  flies.  The 
phthisical  patient  often  infects  his  alimentary  tract 
by  swallowing  his  own  sputum. 

Infection  by  inoculation  —  through  abrasions  of 
the  skin  —  is  not  common  and  is  usually  localized. 

Modes  of  Dissemination  and  Methods  of  Preven- 
tion. —  To  the  nurse  the  modes  of  dissemination 
and  the  methods  employed  for  the  prevention  of 
tuberculous  infection  are  of  double  interest,  on  her 
own  account  as  well  as  that  of  her  patients. 

Of  first  importance,  and  which  should  never  be 
forgotten,  is  the  fact  that  "  every  tuberculous  indi- 
vidual is  a  source  from  which  the  disease  may 
be  further  disseminated."  (Abbott.)  The  phthisis 
patient  is  a  source  of  greater  danger  to  his  neighbor 
than  persons  suffering  from  other  forms  of  tubercu- 
losis, but  large  numbers  of  bacilli  are  thrown  off 
from  lupus  (tuberculosis  of  the  skin),  from  wound 
secretions  in  surgical  tuberculosis,  from  evacuations 
from  the  bowels  in  intestinal  tuberculosis,  and  from 


92  BACTERIOLOGY  FOR  NURSES 

the  urine,  when  tuberculosis  of  the  genito-urinary 
tract  is  present. 

In  the  infectious  diseases,  as  diphtheria,  smallpox, 
scarlet  fever,  etc.,  the  duration  of  the  disease  is  short, 
and  isolation  is  compulsory;  but  isolation  in  cases 
of  tuberculosis  has  never  been  compulsory  in  any 
state,  and  as  the  duration  of  the  disease  may  be 
for  many  months  and  sometimes  years,  it  is  easy  to 
understand  the  ready  dissemination  and  the  fright- 
ful extent  of  tuberculous  infections. 

With  intelligent  patients  of  cleanly  habits,  it  is 
easy  to  impress  upon  them  how  they  may  control  the 
spread  of  the  disease  by  the  observation  of  a  few 
simple  details,  but  with  the  ignorant  and  persons 
who  are  unacquainted  with  the  rudiments  of  clean- 
liness, it  is  an  almost  hopeless  task  to  expect  them 
to  respond  to  instruction  upon -these  points.  The 
visiting  nurses  in  all  large  cities,  who  for  years  have 
carried  on  a  systematic  campaign  of  instruction  in 
the  tenements,  make  extremely  discouraging  reports 
of  the  success  of  their  efforts. 

If  the  phthisis  patient  can  be  persuaded  to  use  the 
cheap  paper  sputum  cup,  which  can  be  burned,  and 
will  use  paper  napkins  or  old  cloths,  which  can  also 
be  burned,  while  he  is  away  from  home,  he  can  elimi- 
nate the  chief  source  of  danger;  but  when  such  a 


TUBERCULOSIS.       LEPROSY  93 

patient  continually  expectorates  upon  the  floor  or 
pavement,  he  is  a  menace  not  only  to  his  family,  but 
to  the  whole  community  in  which  he  lives. 

"Cornet  states  that  for  the  ten  years  ending  with 
1897  the  death  rate  from  consumption  in  Germany 
was  21.5  per  10,000  against  31.4  for  a  corresponding 
previous  period.  He  believes  the  result  due  to  more 
general  efforts  at  the  suppression  of  indiscriminate 
spitting  and  more  care  in  preventing  tuberculous 
sputum  from  becoming  dried  and  disseminated 
through  the  air  as  dust."  (Abbott.) 

The  prejudice  against  the  establishment  of  sana- 
toria for  the  segregation  of  tuberculous  patients 
who  are  unable  to  have  proper  care  and  control 
for  the  protection  of  their  families,  is  gradually 
dying  out  as  general  intelligence  upon  the  subject 
increases,  and  many  such  institutions  are  being  built 
in  the  large  cities,  while  camps  and  cottage  hospitals 
for  incipient  cases  in  all  parts  of  the  country  are 
restoring  health  to  thousands. 

The  whole  system  for  the  prevention  of  tuberculo- 
sis may  be  summed  up  in  a  very  few  words,  viz. 
sunlight,  fresh  air,  and  cleanliness,  but  in  the  last 
lies  the  great  stumbling  block.  The  practice  of 
cleanliness  must  begin  with  the  infant;  no  adult 
reared  in  unclean  surroundings  can  ever  be  taught 


94  BACTERIOLOGY   FOR   NURSES 

thorough  cleanliness ;  the  compiler  speaks  with  con- 
viction, after  twenty  years  of  experience  in  training 
hundreds  of  nurses,  that  no  woman  who  has  not  been 
taught  the  technique  of  cleanliness  in  her  own  home 
can  or  will  ever  be  thoroughly,  consistently,  and 
safely  clean  in  her  nursing  technique.  If  this  be  true 
of  women  of  the  better  class,  we  should  have  infinite 
patience  with  the  poor  and  ignorant  who  come  from 
generations  of  poverty  and  its  accompanying  filth. 
If  the  tuberculous  patient  remains  in  his  own  home, 
he  should  never  occupy  a  room  with  any  other  person, 
his  dishes  should  be  kept  apart  and  any  broken  food 
should  be  burned,  his  bed  and  body  linen  should  be 
changed  frequently,  and  the  mattress,  blankets,  and 
pillows  should  be  hung  out  in  the  air  every  sunny  day, 
and  if  he  be  confined  to  his  bed,  enough  bedding 
should  be  provided  to  use  alternately.  Paper 
sputum  cups  are  preferable,  as  they  may  be  burned, 
and  if  metal  cups  are  used,  they  should  be  lined  with 
two  thicknesses  of  rather  heavy  paper,  which  can  be 
removed  with  the  sputum  and  put  into  the  fire,  and 
the  cup  be  boiled  for  ten  minutes  in  a  5  per  cent 
soda  solution,  and  immersed  in  a  5  per  cent  solution 
of  carbolic  acid  until  needed  again;  there  should 
always  be  two  cups  for  alternate  use.  Old  soft  cotton 
or  linen  cloth  or  cheese  cloth  should  be  used  for 


TUBERCULOSIS.       LEPROSY  95 

handkerchiefs  and  always  burned ;  these  should  be 
small  and  should  never  be  put  into  the  pocket,  but 
rolled  up  tightly  in  paper  immediately  after  using. 
Kissing,  caressing,  or  shaking  hands  should  be  for- 
bidden. Dry  dusting  should  never  be  done,  but  all 
furniture  and  woodwork  wiped  off  daily  with  a 
dusting  cloth  wet  with  a  5  per  cent  solution  of  car- 
bolic acid.  Floors  should  be  bare  and  washed  every 
day  if  possible. 

The  practice  of  establishing  the  tuberculous  pa- 
tient in  a  tent  or  upon  a  broad  porch  is  not  only  the 
best  possible  thing  for  the  patient,  but  for  the  safety 
of  the  family.  Even  in  the  city  or  large  towns  such 
patients  may  be  made  comfortable  for  six  or  seven 
months  of  the  year. 

The  infection  of  old  houses  and  apartments  with 
the  tubercle  bacilli  must  become  a  recognized  fact, 
the  old  woodwork,  especially  floors,  and  old  wall 
paper  probably  being  the  lurking  places.  In  Paris 
statistics  were  compiled  showing  that  certain  blocks 
and  localities  of  the  city  had  been  furnishing  a  con- 
tinuous stream  of  tuberculous  patients  for  many  years, 
proving,  without  doubt,  that  the  old  buildings  were 
the  source  of  danger. 

Clean  hands  and  clean  handkerchiefs  are  the  nurse's 
best  protection  while  caring  for  tuberculous  patients. 


96  BACTERIOLOGY    FOR   NURSES 

Predisposing  Causes  of  Tuberculosis.  —  It  is  said 
that  in  no  other  known  disease  do  predisposing  fac- 
tors figure  so  largely  as  in  tuberculosis. 

Indoor  occupations  under  unsanitary  conditions, 
such  as  bad  air,  insufficient  light,  dampness,  and  long 
hours  of  work,  are  especially  conducive  to  all  forms 
of  tuberculosis.  It  was  formerly  thought  that  by 
heredity  many  persons  were  tuberculous,  but  this  is 
now  disputed,  and  it  is  believed  that  the  intimate 
relations  of  parents  and  children  living  under  the 
same  conditions  accounts  for  the  infection.  Alcohol- 
ism, with  all  that  goes  with  it,  is  a  predisposing  factor, 
also  the  wasting  diseases,  as  diabetes  and  typhoid 
fever,  are  often  followed  by  phthisis,  but  the  most 
important  factor  of  all  is  uncleanliness  combined 
with  poor  food  and  bad  air  in  the  homes. 

Tuberculin.  —  In  1890  Robert  Koch  announced 
his  preparation  known  as  Tuberculin  R.  as  a 
curative  agent.  Tuberculin  is  the  filtered  products 
of  growth  from  cultures  of  tubercle  bacilli.  When 
injected  under  the  skin  of  a  healthy  person,  no  re- 
action occurs,  but  when  used  upon  a  tuberculous  per- 
son or  animal,  a  pronounced  reaction  occurs,  consisting 
of  a  sudden  elevation  of  temperature  and  a  marked 
hypera^mia  about  the  tuberculous  focus,  followed 
by  disintegration  of  the  tuberculous  mass. 


TUBERCULOSIS.       LEPROSY  97 

The  use  of  tuberculin  did  not  prove  as  satisfactory 
as  Koch  had  expected,  and  was  discontinued  almost 
entirely,  except  as  a  means  of  diagnosis  in  obscure 
cases  in  man  and  as  a  test  in  dairy  cows,  the  latter 
being  practiced  extensively  in  all  countries. 

Immunity.  —  An  attack  of  tuberculosis  followed 
by  cure  does  not  render  the  patient  immune,  but  on 
the  contrary,  seems  to  increase  his  susceptibility  to 
further  infections. 

LEPROSY 

Leprosy  is  a  chronic,  infectious,  endemic  disease 
caused  by  Bacillus  leprce,  an  organism  bearing  a  very 
strong  resemblance  to  Bacillus  tuberculosis. 

The  leprosy  bacillus  was  discovered  by  Hansen,  a 
Norwegian  scientist,  in  1872 ;  prior  to  this,  certain 
peculiar  cells  had  been  observed  in  leprous  tissue, 
and  Hansen  found  large  numbers  of  leprosy  bacilli 
lying  within  these  "kpra  cells."  The  leprosy  bacillus 
is  a  slender  rod,  usually  straight,  occurring  in  charac- 
teristic bundles;  it  is  without  motion,  does  not  form 
spores,  and  is  usually  found  in  the  "lepra  cells,"  al- 
though sometimes  observed  in  the  lymphatic  glands 
and  in  the  blood. 

In  the  tubercular  form  the  bacilli  occur  in  enor- 
mous numbers,  much  greater  than  in  the  anaesthetic 
form. 


98  BACTERIOLOGY   FOR   NURSES 

In  staining  the  bacilli  of  leprosy  the  reaction  may 
be  said  to  be  identical  with  the  tubercle  bacilli,  but 
this  similarity  and  the  strong  resemblance  in  appear- 
ance do  not  cause  any  confusion  of  the  two  organisms, 
because  the  leprosy  bacillus  is  found  in  the  character- 
istic "lepra  cells,"  and  the  general  symptoms  of  the 
two  diseases  are  widely  different. 

Leprosy  in  Man.  —  Leprosy  is  most  common  in 
Asia  and  Africa  along  the  seacoasts,  but  it  also 
occurs  in  certain  areas  of  Greece,  Russia,  Norway, 
the  West  Indies,  the  Pacific  islands,  and  in  North 
America  in  Nova  Scotia,  southern  California 
(among  the  Chinese),  and  in  Minnesota,  —  being  in- 
troduced into  Minnesota  from  Norway. 

Leprosy  is  manifested  in  two  forms :  "  tubercular," 
which  is  characterized  by  nodules  of  the  skin  and 
mucous  membranes;  and  the  " anaesthetic"  form,  in 
which  the  sensory  nerves  are  first  involved.  In  the 
earliest  stage  the  nerves  are  hypersensitive,  followed 
by  the  anaesthetic  period,  which  is  accompanied  by  a 
dry  scaly  eruption  of  the  skin  of  the  back,  shoulders, 
arms,  around  the  root  of  the  nails,  and  following  the 
course  of  the  nerves. 

The  anaesthetic  form  is  more  common  in  the  tropics, 
and  a  mixture  of  the  two  varieties  is  not  infrequent. 

Both  types  of  the  disease  are  characterized  by 


TUBERCULOSIS.      LEPROSY  99 

extreme  disfigurement :  in  the  tubercular  type  the 
nodular  growths,  especially  about  the  face,  often 
present  an  oozing,  loathsome  surface;  and  in  the 
anaesthetic  form  necrosis  and  the  separation  of  the 
parts  occur. 

While  there  seems  to  be  no  doubt  of  the  infective- 
ness  of  leprosy,  no  conclusion  has  been  reached 
regarding  the  avenue  of  infection.  The  disease 
shows  little  tendency  to  extend  beyond  the  areas 
where  it  is  endemic,  and  many  healthy  persons  have 
lived  for  years  among  the  lepers  without  contracting 
the  disease. 

Negroes  are  more  susceptible  to  leprosy  than 
whites. 

Many  authorities  believe  that  the  disease  is 
hereditary,  but  equally  good  authorities  strongly 
dispute  the  point. 

All  efforts  to  reproduce  the  disease  in  man  by  in- 
oculation have  failed  entirely,  and  in  only  a  few  in- 
stances has  the  disease  been  reproduced  in  any  animal. 

In  most  countries  the  segregation  of  lepers  into 
colonies  has  lowered  the  number  of  cases,  but 
statistics  are  somewhat  misleading,  as  it  is  a  well- 
known  fact  that  many  lepers  have  concealed  the 
evidences  of  the  disease  for  years  rather  than  be 
separated  from  their  own  people. 


CHAPTER  X 

GLANDERS,  ACTINOMYCOSIS,  ANTHRAX 

Glanders  is  a  disease  peculiar  to  the  horse,  the 
mule,  and  the  ass,  although  other  domestic  animals 
and  the  animals  in  menageries  and  zoological  gardens 
are  sometimes  affected.  Man  is  susceptible  to  the 
infection  of  glanders,  but  the  cases  are  uncommon 
and  usually  confined  to  veterinarians  and  others 
caring  for  horses,  who  contract  the  disease  by  inocu- 
lation. 

The  glanders  bacillus  was  discovered  by  Loffler  in 
1 882,  and  is  known  as  Bacillus  mallei.  It  is  a  small  rod 
with  rounded  ends,  somewhat  resembling  the  tubercle 
bacillus  except  that  it  is  uniformly  thicker ;  it  is  non- 
motile  and  does  not  form  spores.  In  cultures  the 
B.  mallei  occur  mostly  in  pairs  or  very  short  chains. 
The  bacillus  stains  with  aniline  dyes  and  grows 
readily  upon  ordinary  culture  media,  growth  being 
more  abundant  in  subcultures  than  in  the  first 
transfer  from  the  animal  tissues. 
100 


GLANDERS  101 

B.  mallei  is  easily  destroyed  by  heat  and  by  chemi- 
cals. 

Glanders  may  occur  in  acute  or  chronic  form,  the 
acute  form  being  ushered  in  by  a  chill  and  high 
temperature,  followed  in  a  few  days  by  an  inflamma- 
tion of  the  mucous  membranes  of  the  nose,  and  later 
showing  nodules  and  greatly  enlarged  glands  in 
different  parts  of  the  body.  Death  usually  occurs 
in  a  few  days.  Mules  and  asses  suffer  more  often 
with  the  acute  form  than  horses,  the  latter  usually 
being  afflicted  with  the  chronic  form,  in  which  there 
is  a  profuse  infectious  catarrhal  discharge  from  the 
nose. 

The  infection  of  glanders  through  the  skin  is 
known  as  " farcy,"  and  is  characterized  by  swelling 
and  nodules  of  the  lymphatic  glands.  The  nodules 
in  both  forms  of  glanders  become  softened  and  turn 
into  ulcers.  The  bacilli  are  found  in  the  young 
nodules,  in  the  nasal  discharges,  and  in  acute  general 
infection  may  be  found  in  the  blood. 

Glanders  Infection  in  Man.  —  Grooms  and  others 
working  with  horses  are  most  liable  to  contract  glan- 
ers,  and  several  instances  are  recorded  of  the  infec- 
tion of  laboratory  workers.  Man  rarely  contracts 
the  chronic  form,  and  death  usually  terminates  the 
acute  form  in  about  two  weeks. 


102      .  BACTERIOLOGY   FOR   NURSES 

Entrance  to  the  body  of  the  horse  is  probably 
through  an  abrasion  of  the  nasal  membranes,  or  by 
way  of  the  alimentary  tract,  and  more  rarely  through 
the  broken  skin,  while  in  man  nearly  all  cases  are 
the  result  of  entrance  through  abrasions. 

An  attack  of  glanders  does  not  confer  immunity 
upon  either  man  or  beast. 

The  mattein  test  as  a  means  of  diagnosis  is  used  in 
the  same  way  that  tuberculin  is  employed  for  the 
diagnosis  of  tuberculosis  in  cows.  Mallein  is  the 
filtered  products  of  the  growth  of  B.  mallei. 

ACTINOMYCOSIS 

A  disease  known  as  "  lumpy  jaw,"  which  is 
common  to  cattle  and  occasionally  seen  in  man, 
is  due  to  a  fungus-like  organism  known  as  acti- 
nomyces. 

When  growing  in  colonies  the  fungus  presents  a 
raylike  appearance  resembling  a  rosette  which  is 
discernible  to  the  naked  eye.  The  outer  ends  of  the 
films  forming  the  rosette  are  sometimes  blunt  or 
"clubbed." 

The  staining  and  cultivation  of  actinomyces  is 
attended  with  considerable  difficulty. 

Much  discussion  has  been  spent  upon  the  ques- 
tion as  to  whether  there  are  two  distinct  species  of 


ACTINOMYCOSIS  103 

actinomyces  in  man  and  in  the  lower  animals,  but 
it  is  supposed  now  that  only  one  exists. 

In  cattle  actinomycosis  is  characterized  by  the 
presence  of  hard  swellings  in  and  about  the  head, 
particularly  in  the  tongue  and  lower  jaw,  which 
gradually  soften,  destroying  the  bones  as  well  as 
the  soft  parts,  while  the  swelling  continues  to  en- 
croach upon  the  surrounding  tissues,  usually  causing 
great  disfigurement.  Death  is  usually  due  to  the 
mechanical  obstruction  caused  by  the  hard  tumors, 
and  not  to  any  toxic  effect  of  the  bacteria. 

In  man  the  infection  is  more  general,  with  less 
formation  of  the  hard  tumors,  and  more  suppura- 
tion, death  usually  occurring  in  a  few  weeks. 

Method  of  Infection.  —  The  actinomyces  is  found 
upon  grain,  barley  especially,  which  would  probably 
account  for  the  infection  of  cattle;  but  the  manner 
of  transmission  from  one  animal  to  another  or  to 
man  has  not  yet  been  explained.  The  cases  occur- 
ring in  man  have  often  been  in  persons  who  have  had 
no  contact  or  remote  relation  to  either  animals  or 
men  suffering  with  the  disease,  and  neither  have  they 
handled  any  grain  which  might  harbor  the  organ- 
isms. 


1(H  BACTEEIOLOGY   FOR  NURSES 

ANTHRAX 

Splenic  fever  or  anthrax  is  a  disease  of  cattle, 
sheep,  horses,  and  swine,  caused  by  the  anthrax 
bacillus  (B.  anthracis).  Man  is  also  susceptible  to 
anthrax,  contracting  the  disease  by  inoculation  from 
handling  hides,  wool,  or  the  carcasses  of  animals 
dead  from  anthrax. 

As  early  as  1850  several  investigators  declared 
that  in  the  blood  of  all  animals  suffering  from  anthrax 
were  to  be  found  rodlike  organisms,  and  that 
healthy  animals  which  were  inoculated  with  this 
blood  speedily  manifested  the  typical  symptoms  of 
anthrax. 

It  was  not  until  1876,  when  Robert  Koch  made  his 
first  contribution  to  bacteriology,  that  these  first 
theories  were  proven  by  Koch's  success  in  obtaining 
a  pure  culture  from  which  he  made  many  genera- 
tions of  subcultures,  and  successfully  inoculated 
animals  from  the  last  cultures.  It  was  at  this  time 
that  Koch  made  the  first  observations  upon  spore- 
formation  in  bacteria. 

The  Bacillus  anthracis  is  one  of  the  largest  of  the  dis- 
ease producing  bacteria;  it  occurs  singly  or  in  short 
chains,  and  shows  a  capsule  which  in  the  short  chains 
appears  to  envelop  the  whole  chain  in  one  capsule. 


AXTHRAX  105 

Colonies  of  anthrax  bacilli  present  an  extraordi- 
nary appearance,  not  unlike  wavy  locks  of  hair.  The 
staining  and  cultivation  of  the  bacillus  is  not  difficult. 

Growth  is  best  at  a  temperature  of  35°  C.  (95°  F.). 
Without  spores  the  anthrax  bacillus  displays 
little  resistance  to  heat,  drying,  or  chemicals,  but 
will  survive  freezing;  but  the  spores  are  the  most 
resistant  of  any  pathogenic  bacteria,  it  being  said 
that  anthrax  spores  have  retained  their  vitality  for 
thirty  years.  The  bacillus  grows  without  oxygen, 
but  no  spore-formation  takes  place  in  the  absence  of 
oxygen.  It  is  believed  that  the  spores  of  the  anthrax 
bacillus  never  form  in  the  body  of  the  animal  suffer- 
ing with  anthrax,  but  develop  in  the  discharges  from 
the  body,  or  in  blood  drawn  from  the  body,  or  in  the 
body  after  death.  The  last  reason  is  one  of  especial 
importance,  for  with  the  ordinary  burial  the  spores 
might  retain  their  vitality  in  the  soil  for  years.  It  is 
customary  to  cover  the  carcasses  of  animals  dead  from 
anthrax  with  large  quantities  of  lime,  which  effectu- 
ally prevents  spore-formation.  Pastures  which  have 
been  used  by  infected  cattle  are  declared  to  be  un- 
safe after  ten  or  fifteen  years. 

The  usual  method  of  infection  for  cattle  is  by 
grazing  in  infected  pastures.  Epidemics  of  anthrax 
have  occurred  as  the  result  of  pastures  being  over- 


106  BACTERIOLOGY   FOR   NURSES 

flowed  by  drainage  from  tanneries,  hides  from  foreign 
countries  often  being  infected. 

Cattle  may  also  be  infected  by  inoculation  through 
the  broken  skin,  but  this  occurs  less  often  than 
through  the  alimentary  tract. 

The  Infection  of  Anthrax  in  Man.  —  Butchers, 
herders,  and  handlers  of  hides  and  wool  are  most 
commonly  infected  with  B.  anthracis,  the  infection 
occurring  through  the  broken  skin,  through  the 
respiratory  tract,  or  through  the  alimentary  tract, 
the  disease  in  nearly  all  instances  being  contracted 
from  the  lower  animals,  and  not  from  one  man  to 
another. 

The  most  common  form  of  anthrax  in  man  is  the 
malignant  pustule  or  carbuncle,  contracted  by 
handling  infected  hides  or  carcasses.  This  infection 
is  usually  localized,  and  with  proper  surgical  care 
produces  no  serious  results. 

"Wool  sorter's  disease"  is  a  form  of  anthrax 
contracted  by  inhalation  of  spores  floating  in  the 
air  from  infected  wool.  This  form  of  anthrax  very 
commonly  develops  into  a  general  septicaemia 
resulting  in  death. 

Anthrax  contracted  through  the  alimentary  tract 
is  of  rare  occurrence  in  man,  and  probably  occurs 
from  taking  food  which  has  been  infected  by  han- 


ANTHRAX  107 

dling,  or  more  rarely  from  under-cooked  meat  from 
anthrax-infected  cattle. 

A  vaccine  for  the  immunization  of  herds  and  flocks 
of  cattle,  horses,  and  sheep  has  been  very  successfully 
employed  in  Europe  and  South  America,  where  an- 
thrax prevails  much  more  than  in  the  United  States. 


CHAPTER  XI 

TYPHOID  FEVER (ENTERIC  FEVER) 

TYPHOID  fever  is  an  acute  infectious  disease 
characterized  by  lesions  or  ulcerations  in  the  small 
intestines,  and  by  symptoms  of  profound  intoxica- 
tion often  resembling  general  septicaemia,  which  is 
due  to  the  Bacillus  typhosus.  The  bacillus  of  ty- 
phoid was  discovered  by  Eberth  in  1880,  and  isolated 
first  by  Gaffky  in  1884.  The  B.  typhosus  belongs 
to  a  group  of  organisms  (colon-typhoid  bacilli) 
bearing  a  strong  resemblance,  which  makes  identifica- 
tion often  a  matter  of  great  difficulty.  In  the  intes- 
tines of  all  healthy  individuals  are  found  the  Bacillus 
coli,  which  is  ordinarily  a  harmless  saprophyte,  but 
closely  resembles  the  B.  typhosus  both  in  appear- 
ance and  habits  of  growth.  The  other  organisms 
comprising  the  group  are  the  para-typhoid  bacilli, 
the  bacillus  of  dysentery,  the  Bacillus  enteriditis,  the 
Psittacosis  bacillus,  the  bacillus  of  hog  cholera,  and 
others. 

108 


TYPHOID   FEVER  109 

In  size  the  bacillus  of  typhoid  is  about  three  times 
as  long  as  it  is  broad,  the  rods  having  rounded  ends, 
but  with  very  little  in  its  appearance  to  aid  in  its 
identification.  It  is  very  actively  motile,  but  the 


FIG.  18.  —  Bacillus  Fra.  19.  —  Bacillus  typhosus, 

typhosus.  showing  flagella. 

flagella  cannot  be  seen  without  special  staining 
(Loftier 's  method).  During  life  the  bacilli  may  be 
found  in  the  blood,  in  the  urine,  in  the  rose-spots,  and 
in  the  feces  of  patients  suffering  with  typhoid  fever; 
and  after  death  may  be  found  in  the  tissues  of  the 
spleen,  of  the  liver,  of  the  kidneys,  and  of  the  intes- 
tines. Colonies  of  typhoid  bacilli  show  nothing  es- 
pecially characteristic,  being  irregular,  with  somewhat 
wrinkled  surfaces  and  a  blue  white  color.  Typhoid 
bacilli  grow  best  at  about  35°  C.  (95°  F.);  they 
are  killed  by  a  temperature  of  60°  C.  (140°  F.),  but 
sometimes  survive  freezing  for  weeks  or  even  months. 
They  grow  slowly,  with  or  without  oxygen,  and  form 
no  spores;  their  growth  does  not  liquefy  gelatin, 
nor  produce  gaseous  fermentation,  nor  coagulate 
sterilized  milk;  these  points  and  others  are  utilized 


110  BACTERIOLOGY    FOR    NURSES 

to  distinguish  B.  typhosus  from  the  allied  organisms 
which  so  closely  resemble  it. 

While  the  bacillus  of  typhoid  is  frequently  found  in 
soil  and  in  water,  its  presence  can  always  be  traced 
to  the  discharge  of  excreta  from  typhoid  fever 
patients;  the  origin  is  often  remote  and  obscure,  but 
careful  investigation  invariably  establishes  the  fact 
that  such  pollution  of  soil  and  water  always  arises 
from  the  excreta  of  typhoid-fever  patients. 

It  was  formerly  thought  that  the  bacillus  of  ty- 
phoid was  capable  of  reproduction  in  both  soil  and 
water,  but  this  is  now  acknowledged  to  be  wrong, 
experiments  showing  that,  while  the  bacillus  may 
survive  in  sterile  water  for  three  months  and  in  ordi- 
nary streams  for  five  or  six  days,  it  does  not  multiply 
in  either  case. 

In  the  soil  or  in  privy  vaults,  the  bacilli  may  sur- 
vive for  months,  and  may  then  be  washed  into 
streams  by  heavy  rains,  or  they  may  infect  the  soil 
when  the  contents  of  the  vault  is  used  for  fertilizing 
purposes,  but  they  do  not  multiply  in  the  soil. 

Typhoid  Infection  in  Animals.  —  Repeated  experi- 
ments have  failed  to  produce  the  typical  typhoid 
fever  of  the  human  being  in  animals,  although  infec- 
tions have  occasionally  occurred. 

Prevalence  of  Typhoid  Fever.  —  Typhoid  fever  is 


TYPHOID   FEVER  111 

one  of  the  widespread  diseases,  which  has  been  char- 
acterized by  appalling  epidemics.  As  the  disease  is 
contracted  by  taking  the  germs  into  the  mouth,  and 
as  the  organisms  originate  only  in  the  feces  and 
urine  of  typhoid-fever  patients,these  epidemics  are  a 
sad  comment  upon  our  private  and  public  cleanliness. 

The  fever  prevails  mostly  in  August,  September, 
and  October,  favored  no  doubt  by  the  beginning  of 
decay  in  vegetation ;  it  is  more  common  in  men  than 
women,  probably  because  more  men  drink  water 
from  varied  sources  than  women;  it  occurs  more 
frequently  between  the  ages  of  sixteen  and  thirty- 
five  than  at  any  other  time. 

Symptoms  of  Typhoid  Fever.  —  The  symptoms  of 
typhoid  fever  are  widely  different  in  different  indi- 
viduals, in  fact  so  varied  that  diagnosis  is  often  a 
matter  of  great  difficulty. 

The  premonitory  symptoms  are  commonly  head- 
ache, malaise,  loss  of  appetite,  nosebleed,  and  the 
gradual  increase  of  temperature.  About  the  tenth 
day  characteristic  rose-spots  appear  upon  the 
abdomen.  The  onset  is  usually  gradual,  but  in  some 
instances  is  as  sudden  and  violent  as  a  typical  pneu- 
monia. 

During  and  after  the  second  week,  suppurations 
may  occur  in  various  parts  of  the  body,  which  may 


112  BACTERIOLOGY   FOR   NURSES 

be  attributed  to  the  bacillus  of  typhoid.  Mixed 
infections  also  are  not  uncommon,  the  pus  cocci  and 
the  pneumococci  frequently  causing  serious  or  fatal 
complications. 

Modes  of  Dissemination.  —  Typhoid  fever  may  be 
disseminated  by  polluted  water,  food,  and  soil,  each 
factor  carrying  the  bacilli  in  an  infinite  number  of 
ways,  which  are  often  so  circuitous  that  to  the  igno- 
rant they  seem  to  be  very  " far-fetched."  Air-borne 
infection  is  rare. 

Water  pollution  in  cities  and  towns  is  always  the 
result  of  a  close  relation  between  the  water  supply 
and  the  disposal  of  sewage;  the  same  statement 
holds  good  in  villages  and  farms  where  the  water 
comes  from  shallow  wells  in  close  proximity  to  privy 
vaults.  For  twenty  years,  ending  about  1893, 
typhoid  fever  prevailed  to  an  alarming  extent  in 
Chicago,  where  the  city  sewage  was  discharged  into 
Lake  Michigan  and  the  city  water  was  drawn  from 
the  same  source  from  intakes  at  one  half  and  one 
mile  from  shore.  The  prevalence  culminated  in  a 
severe  epidemic  in  1892,  when  in  Cook  County  Hospi- 
tal alone  there  were  two  hundred  and  forty  typhoid- 
fever  patients  on  August  1. 

During  the  following  year  a  new  three-mile  intake 
was  opened,  and  soon  after  the  drainage  canal  which 


TYPHOID   FEVER  113 

diverted  the  sewage  into  the  Illinois  River  was  also 
opened,  with  the  result  that  with  a  greatly  increased 
population  the  number  of  typhoid-fever  patients  in 
Cook  County  Hospital,  August  1, 1894,  had  dropped 
to  less  than  forty. 

The  history  of  epidemics  of  typhoid  fever  due  to 
polluted  water  —  and  they  are  only  too  numerous 
—  are  strikingly  similar;  somehow,  by  some  way, 
the  water  supply  and  the  sewage  come  into  contact, 
and  if  the  sewage  contains  the  discharges  from  many 
typhoid-fever  patients,  the  possibilities  of  epidemics 
are  enormous. 

While  freezing  kills  a  majority  of  typhoid  bacilli, 
enough  survive  to  make  the  ice  made  from  polluted 
water  a  source  of  danger. 

M ilk,  more  than  any  other  article  of  food,  serves  as 
a  carrier  of  typhoid  bacilli,  because  no  other  article 
of  food  is  subjected  to  so  much  or  so  careless  hand- 
ling, nor  does  any  other  article  of  food  furnish  such 
favorable  media  for  the  development  of  all  kinds 
of  bacteria.  Although  the  bacillus  of  typhoid  does 
not  multiply  in  water,  it  is  reproduced  in  milk. 

The  use  of  polluted  water  for  washing  milk  cans, 
bottles,  pails,  and  measures  is  the  common  source  of 
milk  pollution  with  typhoid  bacilli. 

Uncooked  food,  such  as  lettuce,  celery,  cucumbers, 
radishes,  tomatoes,  water  cress,  and  raw  oysters  are 


114  BACTERIOLOGY   FOR   NURSES 

often  the  source  of  infection,  either  from  the  use 
of  polluted  water  in  cleaning  .them,  or  from 
fertilizers. 

Houseflies  are  a  frequent  cause  of  the  contamina- 
tion of  both  food  and  dishes.  It  has  been  shown 
experimentally  that  living  typhoid  bacilli  may  re- 
main in  or  upon  the  bodies  of  houseflies  for  two  or 
three  weeks. 

Infection  from  contact  does  not  result  from  casual 
contact,  but  usually  occurs  in  nurses  who  are  caring 
for  typhoid-fever  patients,  and  for  this  reason  the 
most  careful  disinfection  must  be  given  to  the  urine, 
the  fecal  discharges,  and  to  the  bed  and  body  linen  of 
all  typhoid  patients.  The  details  of  the  nursing  of 
typhoid  patients  are  almost  countless,  requiring  an 
extraordinary  amount  of  handling,  which  renders 
infection  an  easy  matter  unless  the  patient  and  his 
linen  are  kept  immaculately  clean  and  the  nurse 
gives  her  own  hands  the  most  scrupulous  care. 

That  comparatively  few  nurses  contract  typhoid 
fever  from  their  patients  speaks  volumes  for  their 
observation  of  cleanliness. 

A  recent  extraordinary  discovery  regarding  the 
dissemination  of  typhoid  fever  is  the  fact  that  ty- 
phoid bacilli  may  be  found  in  the  excreta  of  some 
person  for  months  or  years  after  an  attack,  which 


TYPHOID    FEVER  115 

no  doubt  explains  some  of  the  hitherto  unexplained 
sources  of  infection.  Attempts  have  been  made  to 
secure  an  internal  disinfection  in  these  cases  to  pre- 
vent further  elimination  of  the  bacilli. 

Immunity  following  an  attack  of  typhoid  fever  is 
variable,  an  occasional  second  or  even  third  attack 
having  been  recorded. 

Persons  coming  from  a  pure  water  supply  to  a 
polluted  water  are  very  susceptible  to  typhoid 
infection ;  while  persons  living  permanently  in  a 
city  having  an  impure  water  are  almost  wholly 
immune. 

The  Widal  Test  is  commonly  employed  as  a  means 
of  diagnosis,  especially  in  cases  lacking  the  character- 
istic clinical  symptoms.  It  was  discovered  by  Widal 
that  if  living  typhoid  bacilli  were  placed  in  the  dilute 
blood-serum  taken  from  a  person  suffering  with  ty- 
phoid fever,  they  would  speedily  lose  their  motility 
and  become  clumped  (agglutinated)  in  characteristic 
groups. 

Serum-therapy.  —  Numbers  of  attempts  have 
been  made  to  treat  typhoid  fever  by  a  specific 
serum,  but  so  far  the  results  have  not  been  successful. 

Vaccination  for  protection  against  typhoid  infec- 
tion has  been  much  more  successful.  The  vaccine 
contains  bacterial  cells  or  substances  derived  from 


116  BACTERIOLOGY   FOR    NURSES 

them.  In  the  British  army  in  India  and  South 
Africa  vaccination  against  typhoid  fever  was  em- 
ployed for  thousands  of  soldiers  and  for  many  nurses, 
the  results  being  fairly  successful.  Wonderful  re- 
sults were  obtained  in  our  own  Army  during  the  ma- 
neuvers of  1911  at  San  Antonio,  and  again  in  Texas 
City  in  1913,  where  thousands  of  soldiers  were 
vaccinated.  In  1911,  12,800  men  wrere  in  camp  for 
four  months,  and  only  one  case  of  typhoid  fever 
occurred,  and  at  the  present  time  (January,  1914) 
no  cases  have  thus  far  occurred  among  the  troops 
assembled  in  Texas. 


CHAPTER  XII 

DIPHTHERIA 

DIPHTHERIA  is  an  infectious  disease  caused  by  the 
Bacillus  diphtheria,  which  was  discovered  by  Klebs 
in  1883  and  first  isolated  by  Loffler  in  1884,  hence  the 
name,  Klebs-Loffler  bacillus  of  diphtheria. 

An  enormous  amount  of  research  has  been  applied 
to  the  bacillus  of  diphtheria  and  its  toxins,  which  led 
to  the  discovery  and  use  of  an  antitoxin  serum  for 
the  prevention  and  cure  of  diphtheria,  that  may  be 
considered  one  of  the  most  important  contributions 
of  bacteriology  to  medical  science. 

Bacillus  diphtherice  is  a  slender  rod  varying  in 
length  from  1  /u,  to  6  //.,  presenting  a  beaded  or  gran- 
ular appearance  and  sometimes  showing  clubbed 
ends.  No  other  known  bacillus  shows  so  great  a 
variety  of  shapes  and  sizes,  nor  in  artificial  media 
produces  so  many  involution  (abnormal)  forms. 

The  diphtheria  bacillus  does  not  form  spores  and 
has  no  power  of  motion. 

117 


118  BACTERIOLOGY   FOR  NURSES 

Many  special  methods  of  staining  the  organism 
are  used.  The  diphtheria  bacillus  grows  best  upon 
a  slightly  alkaline  medium  at  body  heat,  37°  C.  (98.6° 
F.),  often  showing  minute  colonies  within  twelve  or 
fifteen  hours,  which  are  of  a  grayish  white  color  with 
granular  surfaces  and  fringed  edges. 

Resistance.  —  The  resistance  of  the  diphtheria 
bacillus  constitutes  one  of  its  chief  dangers  as  an 
infective  agent.  Growths  upon  ordinary  media 
retain  their  vitality  from  six  weeks  to  twelve  or  fifteen 
months,  and  observers  have  isolated  living  bacilli 
from  dried  diphtheritic  membrane  after  a  lapse  of 
eight  months.  It  is  said  that  bacilli  in  dry  membrane 
will  resist  dry  heat  at  98°  C.(208.4°  F.)  for  an  hour, 
but  will  be  killed  by  moist  heat  at  55°  C.  (131°  F.) 
in  forty-five  minutes. 

This  extreme  resistance  probably  explains  many 
instances  of  outbreaks  of  diphtheria  of  unknown 
origin,  as  the  bacilli  could  easily  be  carried  in  the 
dry  state  for  long  distances  by  means  of  clothing 
and  many  other  articles. 

Diphtheria  Infection  in  Man.  — The  mucous  mem- 
branes of  the  human  body  are  the  favorite  site  for 
the  development  of  the  bacilli  of  diphtheria.  The 
pharynx  is  most  commonly  infected,  but  the  larynx 
or  nasal  membranes  are  quite  often  the  site  of  infec- 


DIPHTHERIA  119 

tion,  while  infection  of  the  conjunctiva  (membrane 
of  the  eye),  and  the  mucous  membranes  of  the  genital 
organs  is  not  uncommon. 

Diphtheria  is  a  typical  toxaemia;  the  bacillus  is 
almost  never  found  anywhere  outside  of  the  point  of 
infection,  which  shows  a  false  membrane  accom- 
panied by  necrosis  of  the  tissues  beneath  it  and  a 
profuse  exudate,  while  the  general  symptoms  indi- 
cate grave  lesions  of  the  heart,  the  nervous  system, 
and  the  kidneys. 

Fatty  degeneration  of  the  heart  and  nervous  system 
causes  the  extreme  weakness  and  prostration  so 
frequently  observed  in  diphtheria,  as  well  as  the 
attacks  of  paralysis  following.  The  gravity  of  a 
diphtheritic  infection  cannot  be  measured  by  the  ex- 
tent of  the  false  membrane,  as  many  fatal  results 
follow  apparently  mild  cases,  showing  that  a  small 
amount  of  toxin  may  do  fatal  damage  to  vital  organs. 
McCollom  says,  "A  patch  of  membrane  the  size  of  a 
thumb-nail  on  the  tonsil  may  generate  sufficient 
toxin  to  cause  death." 

In  most  instances  the  Bacillus  diphtheria  is  not 
alone  in  causing  an  infection,  but  is  associated  with 
the  pyogenic  organisms,  the  streptococcus  pyogenes 
occurring  oftenest,  the  staphylococcus  and  pneumo- 
coccus  being  found  occasionally. 


120  BACTERIOLOGY    FOR    NURSES 

Some  of  the  very  serious  complications  of  diph- 
theria, as  the  extensive  swelling  and  suppuration  of 
the  glands  of  the  neck,  are  due  to  pus  infections; 
apparently  the  diphtheritic  lesion  affords  an  avenue 
for  the  entrance  of  pyogenic  organisms.  It  is  in  these 
complicated  cases  of  diphtheria  that  the  antidiph- 
theritic  serum  has  little  effect. 

Diphtheria  Infection  in  the  Lower  Animals.  — By 
inoculation  of  the  lower  animals  typical  diphtheria 
with  all  of  the  local  and  general  symptoms  can  be 
reproduced.  Cats,  dogs,  pigeons,  and  guinea  pigs 
are  the  most  susceptible,  rabbits  somewhat  less  so, 
and  rats  and  mice  the  most  resistant. 

The  Toxins  of  Diphtheria.  —  The  fact  that  the 
bacillus  of  diphtheria  is  found  only  at  the  point  of 
infection  and  not  in  the  internal  organs,  although 
profound  changes  are  wrought  in  these  organs,  led 
to  the  conclusion  that  these  changes  were  due  to  sol- 
uble poisons  (toxins),  produced  by  the  bacilli  at 
the  point  of  infection,  which  gain  access  to  the 
general  circulation  and  are  carried  to  the  distant 
organs  affected.  This  poison  is  known  as  a  toxal- 
bumin,  and  in  its  chemical  composition  is  analogous 
to  the  venom  of  poisonous  serpents.  If  kept  in  the 
dark  at  a  low  temperature,  the  toxin  of  diphtheria 
may  retain  its  activity  for  months,  but  its  toxicity 


DIPHTHERIA  121 

is  lost  by  exposure  to  sunlight  for  a  few  hours  or 
by  boiling  for  five  minutes. 

Animals  inoculated  with  diphtheria  toxin  show  all 
of  the  conditions  of  typical  diphtheria,  except  the 
false  membrane,  which  is  conclusive  evidence  that 
the  chief  injury  arising  from  diphtheria  infection  is 
due  to  the  toxins  secreted  by  the  bacilli. 

The  Antitoxin  of  Diphtheria.  —  In  1890  Behring 
and  Kitasato  found  that  the  blood-serum  of  an  animal 
which  had  been  immunized  against  diphtheria 
would  neutralize  the  effects  of  a  diphtheria  infection 
in  another  animal ;  in  other  words,  the  blood-serum 
of  an  immunized  animal  contained  an  antitoxin 
which  is  now  known  as  the  antitoxin  of  diphtheria. 
By  a  long  series  of  wonderful  experiments  it  was 
found  practical  to  manufacture  the  antitoxin  of 
diphtheria  for  both  protective  and  curative  purposes. 
Horses  are  used  for  this  purpose  on  account  of  their 
size  and  their  endurance.  For  two  or  three  months 
gradually  increasing  doses  of  diphtheria  toxin  are 
injected  subcutaneously  into  the  horse  at  intervals 
of  five  or  six  days.  When  the  blood  has  reached  the 
desired  potency,  it  is  drawn  from  the  jugular  vein  into 
sterile  glasses  and  allowed  to  clot,  when  the  serum  is 
drawn  off  under  aseptic  conditions,  filtered,  tested, 
bottled,  and  kept  in  the  dark  at  a  low  temperature. 


122  BACTERIOLOGY   FOR   NURSES 

For  curative  purposes  the  horse-serum  containing  the 
antitoxin  of  diphtheria,  which  is  commonly  known 
as  anti-diphtheritic  serum,  or  still  more  commonly  as 
diphtheria  antitoxin,  is  injected  with  a  sterilized 
syringe  into  the  loose  subcutaneous  tissue,  usually 
in  the  back,  below  the  shoulder.  Beginning  with  a 
dose  of  3000  or  4000  units,  the  dose  is  repeated  about 
every  six  hours,  the  size  of  the  dose  and  the  number 
of  times  it  is  repeated  being  governed  entirely  by 
the  condition  of  the  patient. 

The  administration  of  diphtheria  antitoxin  is 
sometimes  followed  by  temporary  pains  in  the  joints, 
or  a  rash.  A  few  cases  of  death  from  the  use  of 
diphtheria  antitoxins  are  reported,  the  cause  being  un- 
known, but  is  supposed  to  be  due  to  some  individual 
idiosyncrasy.  In  proportion  to  the  enormous  num- 
ber of  injections  constantly  made  the  deaths  are  of 
very  rare  occurrence. 

The  only  argument  needed  in  favor  of  the  use  of 
diphtheria  antitoxin  is  its  effect  upon  the  death 
rates  from  diphtheria.  In  New  York  the  death  rate 
fell  from  15.19  per  10,000  in  1885  to  6.62  per  10,000 
in  1895;  in  Chicago  from  14.29  per  10,000  in  1885  to 
5.13  per  10,000  in  1895. 

Modes  of  Dissemination.  — Diphtheria  is  more  com- 
mon in  cold  and  temperate  climates  than  in  the 


DIPHTHERIA  123 

tropical  regions,  prevailing  more  in  the  late  autumn 
and  winter  than  at  other  seasons. 

Diphtheria  may  occur  at  all  ages,  but  by  far  the 
greatest  number  of  cases  occur  between  the  third 
and  fifteenth  years  of  life. 

The  dislodgment  of  particles  of  membrane  by 
coughing,  sneezing,  or  labored  breathing  is  the  chief 
source  of  infection  from  the  patient  suffering  with 
diphtheria. 

Nurses  and  doctors  are  liable  to  have  bits  of  mem- 
brane coughed  into  their  faces,  such  accidents  mak- 
ing attendance  upon  diphtheria  patients  peculiarly 
dangerous. 

Epidemics  of  diphtheria  have  been  traced  to  the 
milk-supply,  but  the  pollution  of  milk  does  not  arise 
from  the  cattle,  and  is  always  due  to  outside  human 
sources  during  its  handling. 

It  is  a  popular  belief  that  diphtheria  is  carried  by 
sewer  gas,  but  this  has  not  been  proven  in  any  case. 
Faulty  drainage,  or  leaking  plumbing,  or  accumula- 
tions of  filth  of  any  kind  will  always  afford  means 
of  conveyance  to  bacteria,  and,  in  the  case  of  the 
bacillus  of  diphtheria,  is  especially  dangerous  because 
of  its  unusual  powers  of  resistance. 

The  fact  that  the  diphtheria  bacillus  is  so  resistant 
to  drying  should  be  kept  constantly  in  the  mind  of 


124  BACTERIOLOGY    FOR    NURSES 

the  nurse  in  the  execution  of  all  of  the  details  of 
nursing  a  diphtheria  patient.  Scrupulous  cleanli- 
ness of  bed  and  body  linen,  of  mouth  sponges  and 
dishes,  and  especially  of  the  hands  and  finger  nails 
of  both  the  patient  and  the  nurse,  should  be  observed 
at  all  times. 

Prophylaxis.  —  The  use  of  anti-diphtheritic  serum 
as  a  means  of  protection  against  diphtheria  is  em- 
ployed to  a  considerable  extent  with  well  children 
when  diphtheria  attacks  other  members  of  a  family 
or  school;  the  immunity  thus  acquired  lasts  about 
three  weeks.  The  other  measures  employed  to  pre- 
vent the  further  spread  of  the  disease  are  complete 
isolation  of  the  patient  and  nurse,  the  sterilization  by 
heat  and  chemicals  of  all  clothing,  dishes,  utensils, 
instruments,  etc.,  and  the  consistent  practice  of  clean- 
liness in  the  minutest  details. 

A  common  and  dangerous  mistake  in  the  care  of 
diphtheria  patients  is  to  break  the  quarantine 
directly  the  throat  shows  no  sign  of  membrane.  It  is 
found  that  diphtheria  bacilli  are  present  in  the  throat 
for  days  and  sometimes  weeks  after  convalescence 
seems  fully  established,  consequently  the  patient 
should  be  kept  in  isolation  until  the  throat  is  entirely 
free  from  bacilli.  Some  boards  of  health  require 
two  negative  cultures  for  release  from  quarantine. 


DIPHTHERIA  125 

Pseudo-diphtheria  Bacillus,  or  Hoffman's  Bacillus. 

-  This  organism  was  first  described  by  Hoffman  in 
1888;  it  strongly  resembles  the  bacillus  of  true  diph- 
theria, but  is  non- virulent.  The  pseudo-diphtheria 
bacillus  is  said  to  be  found  in  the  throats  of  about 
20  per  cent  of  all  healthy  persons,  while  only  1  or  2 
per  cent  harbor  the  Klebs-Loffler -bacillus. 


CHAPTER  XIII 

TETANUS,     INFLUENZA,     BUBONIC    PLAGUE 

TETANUS  (lockjaw)  is  an  acute  infectious  disease, 
caused  by  Bacillus  tetani,  which  is  characterized  by 
frequent  and  long-continued  spasms  of  the  voluntary 
muscles,  and  which  is  nearly  always  fatal. 

Bacillus  tetani  belongs  to  the  small  group  of  anae- 
robes, that  is,  the  class  of  microorganisms  which 
grow  best  in  the  absence  of  free  oxy- 
gen, and  is  found  in  abundance  in 
cultivated  soil,  in  street  dust,  and  in 
,    I         the  droppings  of  horses  and  other 
FIG.  20.— Bacillus  animals. 

The  tetanus  bacillus  was  discovered 
by  Nicolaier  in  1884,  who  first  observed  it  in  pus 
taken  from  mice  which  had  been  inoculated  with 
garden  soil.  Nicolaier  did  not  succeed  in  growing 
it  in  pure  cultures,  and  it  was  not  until  1889  that 
Kitasato,  by  the  use  of  anaerobic  methods,  obtained 
cultures  which  were  free  from  other  organisms,  and 

126 


TETANUS  127 

was    able    to    reproduce    the    typical  disease   in 
animals. 

Bacillus  tetani  is  a  rather  long,  slender  6    b 

rod,  and  when  in  the  spore  stage  pre-  '  J  <f  s> 

sents  the  appearance  of  a  small  pin  or  {,  ^s0 

drumstick,  as  the  spore  is  always  situ-  ? 

ated  at  the  extreme  end  of  the  rod,  and  Badiim  tetani 

in  spore  stage. 

is  three  or  four  times  the  size  of  it.     In 
the  vegetative  state  there  is  nothing  characteristic 
in  its  appearance,  but  in  the  spore  stage  it  is  easily 
discerned    among   many   other  organisms,  besides 
being  slightly  motile. 

The  tetanus  bacillus  stains  readily  with  ordinary 
dyes,  but  its  cultivation  is  attended  with  extreme 
difficulty.  Growth  is  slow;  the  first  colonies  not 
showing  before  the  end  of  three  days.  The  growth 
liquefies  gelatin  and  blood-serum,  and  produces  a 
small  amount  of  gas,  giving  out  a  disagreeable  charac- 
teristic odor.  In,  the  vegetative  state  the  bacillus  of 
tetanus  possesses  no  extraordinary  amount  of  resist- 
ance, readily  succumbing  to  heat  and  to  chemicals, 
but  the  spores  of  Bacillus  tetani  possess  wonderful 
powers  of  resistance.  They  will  survive  one  hour 
of  dry  heat  at  80°  C.  (176°  F.)  but  are  killed  by  five 
minutes'  exposure  to  moist  heat  at  100°  C.  (212°  F.), 
They  will  resist  the  action  of  5  per  cent  carbolic  acid 


128  BACTERIOLOGY   FOR   NURSES 

for  ten  hours,  but  are  killed  in  three  hours  by  cor- 
rosive sublimate,  1 : 1000. 

Tetanus  Infection  in  Man.  —  Tetanus  occurs  more 
commonly  in  the  tropics  than  in  colder  climates. 
In  Peru,  Brazil,  and  some  of  the  West  Indian  islands 
tetanus  has  at  times  become  almost  epidemic  in  its 
frequency. 

The  negro  is  particularly  susceptible  to  tetanus, 
whether  from  the  physical  peculiarities  of  his  race 
or  from  his  unclean  habits  has  not  yet  been  deter- 
mined. 

Among  the  negroes  in  hot  climates  tetanus  in  the 
new-born  by  infection  through  the  navel  is  very  fre- 
quent, which  may  be  attributed  to  habits  of  unclean- 
liness. 

Though  an  infectious  disease,  tetanus  is  not  com- 
municable from  one  person  to  another  except  by 
direct  inoculation.  The  disease  can  only  be  con- 
tracted by  the  introduction  of  the  tetanus  bacillus 
into  the  tissues  of  the  body  through  abrasions  or 
wounds. 

The  bacillus  being  strictly  anaerobic,  punctured 
wounds  such  as  occur  by  gunshots,  or  by  stepping 
upon  nails,  splinters,  or  other  sharp  objects  which 
carry  the  bacilli  into  the  deeper  tissues,  where  they 
find  favorable  moisture,  temperature,  and  absence 


TETANUS  129 

of  oxygen  for  their  development,  are  the  most  common 
methods  of  tetanus  infections.  In  wounds  of  this 
character  the  bacillus  of  tetanus  is  not  alone  carried 
into  the  tissues,  as  the  soil  is  filled  with  many  kinds 
of  bacteria,  some  of  which  are  also  infective  and  by 
their  action  create  much  more  favorable  conditions 
for  the  multiplication  of  the  tetanus  bacilli.  Some 
writers,  notably  Kitasato,  believe  that  the  presence  of 
other  bacteria  or  foreign  material  are  necessary  for 
the  production  of  tetanus  in  man. 

Tetanus  may  follow  very  trivial  injuries,  and  as 
the  local  symptoms  are  usually  slight,  the  first 
symptoms  may  be  stiffness  of  the  muscles  of  the 
neck  with  convulsive  seizures.  Like  the  bacillus  of 
diphtheria,  the  tetanus  bacillus  is  found  only  at  the 
point  of  infection,  the  disastrous  effects  to  the  nerv- 
ous system  being  due  to  the  toxins  manufactured 
by  the  bacilli. 

Hundreds  of  cases  of  tetanus  occur  every  year  in 
the  United  States  following  the  celebration  of  the 
Fourth  of  July  with  toy  pistols,  blank  cartridges, 
fire  crackers,  and  other  explosives;  infection  in  these 
instances  usually  occurs  through  injuries  to  the 
hands  from  premature  explosions  which  carry  shreds 
of  clothing  or  cartridge  paper  or  soil  into  the 
tissues. 


130  BACTERIOLOGY    FOR    NURSES 

Tetanus  in  Animals.  —  The  majority  of  the  lowei 
animals  are  susceptible  to  infection  by  the  tetanus 
bacillus,  the  horse  being  particularly  susceptible. 
Cases  are  recorded  of  epidemics  of  tetanus .  in  cer- 
tain stables,  although  there  was  no  evidence  to 
prove  that  the  disease  was  contracted  in  any  way 
than  by  the  inoculation  of  wounds. 

One  peculiarity  of  tetanus  infection  in  animals  is 
the  fact  that  the  convulsive  seizures  begin  near  the 
site  of  infection  and  gradually  become  general,  while 
in  man  the  muscles  of  the  jaw  and  neck  are  always 
affected  first. 

Prophylaxis.  —  All  punctured  or  lacerated  wounds 
of  the  feet  or  in  any  part  of  the  body  which  are  made 
by  gunshots,  nails,  splinters,  or  other  objects  which 
have  been  contaminated  by  the  soil  should  have 
immediate  surgical  care  of  the  most  careful  kind; 
all  discharges  and  dressings  from  the  wounds  of  pa- 
tients suffering  with  tetanus  should  be  burned  at 
once,  and  all  utensils  and  instruments  used  for  such 
dressings  should  be  kept  apart  from  other  surgical 
supplies  and  should  be  sterilized  by  steam  under 
pressure  (autoclave)  after  each  dressing. 

The  Toxin  of  Tetanus.  —  As  in  diphtheria,  the 
tetanus  bacilli  are  found  only  at  the  point  of  in- 
fection, and  the  profound  general  disturbances  are 


TETANUS  131 

due  to  the  soluble  poisons  (toxins)  produced  by 
them. 

Usually  the  wound  shows  little  or  no  redness, 
swelling,  or  suppuration,  and  if  these  conditions  are 
present,  they  prove  the  presence  of  other  organisms. 
This  absence  of  local  signs  constitutes  one  of  the 
gravest  dangers  of  tetanus,  as  there  is  always  a  period 
of  incubation  of  from  seven  to  twelve  days  before 
the  manifestation  of  convulsions,  and  this  lapse  of 
time  makes  treatment  at  this  stage  usually  fruitless. 

Kitasato,  who  first  isolated  Bacillus  tetani,  gives  the 
following  statements  regarding  its  toxic  peculiarities: 
"When  cultures  of  this  organism  are  robbed  of  their 
bacteria  by  filtration  through  porcelain,  the  filtrate 
contains  the  soluble  poison,  and  is  capable,  when 
injected  into  animals,  of  causing  tetanus. 

"  Inoculations  of  other  animals  with  bits  of  the 
organs  of  the  animal  dead  from  the  action  of  the 
tetanus  poison  produce  no  result ;  but  similar  inocu- 
lations with  the  blood  or  with  the  serous  exudate  of 
the  pleural  cavity  always  result  in  the  appearance 
of  tetanus.  The  poison  is  therefore  largely  present  in 
the  circulating  fluids. 

"The  greatest  amount  of  poison  is  produced 
by  cultivation  in  fresh  neutral  bouillon  of  a  very 
slightly  alkaline  reaction. 


132  BACTERIOLOGY   FOR   NURSES 

"The  activity  of  the  poison  is  destroyed  by  an 
exposure  of  one  and  one  half  hours  to  55°  C.  (131° 
F.),  of  twenty  minutes  to  60°  C.  (140°  F.),  and  of  five 
minutes  to  65°  C.  (149°  F.). 

"By  drying  at  the  temperature  of  the  body  under 
access  of  air  the  poison  is  destroyed,  but  by  drying 
at  the  ordinary  temperature  of  the  room  it  is  not 
destroyed. 

"Diffuse  daylight  diminishes  the  intensity  of  the 
poison.  Its  intensity  is  preserved  for  a  much  longer 
time  when  kept  in  the  dark. 

"Direct  sunlight  robs  it  of  its  poisonous  properties 
in  from  fifteen  to  eighteen  hours. 

"Its  activity  is  not  diminished  by  diluting  a  fixed 
amount  with  water  or  nutrient  bouillon. 

"Mineral  acids  and  strong  alkalies  diminish  its 
intensity." 

The  chemical  nature  of  tetanus  toxin  is  not  posi- 
tively known,  but  it  is  one  of  the  most  powerful 
poisons  known. 

Tetanus  Antitoxin  or  Antitetanic  Serum.  —  The 
principles  involved  in  the  production  of  an  antitoxin 
in  diphtheria  are  identical  in  tetanus ;  in  fact,  it  was 
through  the  researches  into  tetanus  that  the  prin- 
ciples were  first  worked  out. 

Animals   are   immunized   from   tetanus   by   the 


TETANUS  133 

repeated  injection  of  gradually  increasing  doses  of 
tetanus  toxin,  until  the  blood  contains  the  required 
amount  of  antitoxin;  the  blood-serum  of  the  immune 
animal  is  capable  of  protecting  the  susceptible 
animal  or  human  from  the  action  of  the  tetanus  toxin 
and  also  against  the  effects  of  the  living  tetanus 
bacillus. 

The  use  of  the  tetanus  antitoxin  for  the  treatment 
of  tetanus  has  been  far  less  successful  than  the  use 
of  diphtheria  antitoxin  for  diphtheria,  because  in 
diphtheria  the  local  signs  in  the  throat  lead  to  an 
early  diagnosis  and  treatment  before  the  bacilli 
have  produced  an  overwhelming  amount  of  toxin; 
while  in  tetanus  the  first  symptoms  are  the  convul- 
sions which  are  due  to  the  presence  of  the  toxins. 
Also,  the  toxins  of  tetanus  have  an  affinity  for  the 
cells  of  the  central  nervous  system,  while  the  toxins 
of  diphtheria  act  upon  the  tissues  of  less  vital  im- 
portance. 

The  other  pathogenic  anaerobes  are  Bacillus 
chauvei,  the  cause  of  a  disease  in  cattle  commonly 
known  as  "black  leg,"  "quarter  evil,"  or  "symptom- 
atic anthrax";  the  Bacillus  edematus,  which  is  the 
cause  of  malignant  edema;  the  Bacillus  Welchii,  or 
gas-producing  bacillus,  found  in  cases  of  emphyse- 


134  BACTERIOLOGY   FOR   NURSES 

matous  gangrene;  the  Bacillus  botulinus,  found  in 
raw  meat  and  the  cause  of  many  cases  of  meat 
poisoning;  and  the  Bacillus  fusiformis,  found  in  an 
affection  of  the  membranes  of  the  mouth  and 
throat. 

INFLUENZA 

Influenza  (commonly  known  as  La  Grippe  or 
Grippe)  is  an  infectious  catarrhal  disease  of  the 
respiratory  tract  caused  by  Bacillus  influenza,  the 
constitutional  symptoms  being  due  to  the  toxins 
produced  by  the  bacilli  growing  in  the  mucous 
membranes,  especially  in  the  bronchii. 

The  influenza  bacillus  is  one  of  the  smallest  known 

pathogenic  organisms,  usually  about  1.5  /i  in  length 

and  0.3  /u,  in  thickness;    the  ends  of  the  rods  are 

rounded,  it  is  strictly  aerobic,  non-motile,  and  does 

•>^N  not  form  spores.     It  stains  with 

x\'t^N       %i\»',       ordinary  dyes  and  is  decolorized 

\*oN,NvVV,     by  the  Gram  method.     It  grows 

VvV-MV  '/\    best  at  body  temperature,  37°  C. 

\'  / 1    |     I      I 

*n\          (98.6°  F.),  but  develops  only  upon 
FIG.  22.— Badiim    media  to   which   blood   has  been 

influenzas.  . 

added.  Being  an  aerobic,  its 
growth  takes  place  only  upon  the  surface  of  the 
medium  employed.  The  colonies  develop  as  minute 


INFLUENZA  135 

transparent  spots,  like  tiny  drops  of  dew.  The 
bacillus  of  influenza  possesses  little  resistance  to 
drying,  to  heat,  or  to  chemicals. 

Influenza  Infection  in  Man.  —  B.  influenza  usu- 
ally invades  the  air-passages  and  is  found  in  the 
sputum  and  nasal  discharges,  more  largely  in  the 
bronchial  mucus;  but  is  almost  never  found  in  the 
blood.  Influenza  bacilli  are  often  found  in  the  bron- 
chial and  nasal  discharges  for  weeks  after  recovery 
seems  complete.  The  varied  symptoms  of  influenza, 
which  seem  to  be  almost  innumerable,  are  due  to  the 
toxins  produced  by  the  bacilli  and  not  to  their  local 
effects. 

Pneumonia,  meningitis,  inflammation  of  the  middle 
ear,  gastric  and  kidney  disorders,  and  many  nerv- 
ous manifestations  very  commonly  accompany  in- 
fluenza, and  "are  probably  to  be  referred  to  the 
selective  action  of  the  toxin  in  different  individuals 
rather  than  to  localization  of  infection."  (Jordan.) 

Pneumonia,  due  to  B.  influenzas,  and  influenza 
as  a  secondary  infection  in  pulmonary  tuberculosis, 
are  both  grave  conditions. 

Pulmonary  tuberculosis  is  not  infrequently  a 
sequence  of  influenza. 

The  methods  whereby  the  bacilli  of  influenza  are 
transmitted  in  the  sudden  and  appalling  epidemics 


136  BACTEKIOLOGY   FOR   NURSES 

of  influenza  which  sometimes  sweep  over  a  whole 
country  in  a  few  days,  and  over  almost  the  whole 
globe  in  a  season,  are  still  matters  of  considerable 
doubt.  The  fact  that  B.  influenza  possesses  so 
little  resistance  to  drying  and  does  not  grow  out- 
side of  the  human  body  does  not  coincide  with  the 
rapidity  of  the  epidemics.  The  fine  droplets  of  mu- 
cus expelled  by  sneezing  and  coughing  would  seem 
to  be  the  source  of  infection,  but  how  they  are  trans- 
mitted such  distances  and  develop  in  so  short  a  time 
remain  to  be  explained. 

Patients  suffering  with  influenza  should  be  iso- 
lated from  other  members  of  the  family.  Particular 
attention  should  be  given  to  the  disinfection  of 
dishes,  utensils,  and  linen.  All  mouth  sponges, 
handkerchiefs,  and  old  linen  used  to  receive  nasal 
and  bronchial  discharges  should  be  burned  at  once. 

An  attack  of  influenza  is  said  to  impart  a  transient 
immunity,  but  it  is  of  such  short  duration  as  to  be 
very  insignificant. 

Influenza  in  Animals.  —  No  typical  attacks  of 
influenza  have  been  reproduced  by  the  inoculation  of 
animals.  Monkeys  and  rabbits  are  the  only  animals 
showing  any  significant  symptoms. 

Pseudo-influenza  Bacilli.  —  Several  bacilli  have 
been  observed  and  described  which  bear  a  strong 


BUBONIC   PLAGUE  137 

resemblance  to  B.  influenza,  but  their  place  has 
not  yet  been  fully  determined. 

An  organism  which  appears  to  be  identical  with  the 
bacillus  of  influenza  is  found  in  whooping  cough. 

The  Koch- Weeks  Bacillus.  —  This  organism  was 
first  observed  by  Koch  in  1883  as  the  cause  of  the 
eye  inflammations  so  common  in  Egypt,  and  later 
was  recognized  as  the  cause  of  the  contagious  form 
of  conjunctivitis,  known  all  over  the  world.  This 
organism  is  slightly  longer  than  the  influenza  bacillus, 
and  may  be  cultivated  without  the  hemoglobin 
medium,  which  are  the  only  points  of  difference 
yet  observed. 

BUBONIC    PLAGUE 

Bubonic  plague,  also  known  as  Oriental  plague, 
bubonic  pest,  black  death,  and  several  other  names,  is 
an  acute,  specific,  transmissible  disease  which  is 
characterized  by  high  fever  and  inflammation  and 
suppuration  of  the  lymphatic  glands  known  as  bu- 
boes, due  to  an  organism  known  as  Bacillus  pestis. 
Bubonic  plague  is  usually  attended  by  high  mortal- 
ity, which  varies  in  different  races  and  in  different 
epidemics. 

While  the  direct  cause  of  bubonic  plague  is  B. 
pestis,  the  predisposing  causes  are  overcrowding, 


138  BACTERIOLOGY   FOR   NURSES 

filth,  bad  air,  poor  and  insufficient  food,  and  intemper* 
ance.  It  may  be  said  that  epidemics  of  plague  have 
never  occurred  where  hygienic  conditions  exist. 

The  plague  bacillus  was  simultaneously  discovered 
and  described  by  Yersin  and  Kitasato  from  observa- 
tions made  during  the  epidemic  at  Hong  Kong  in 
1894.  Plague  bacilli  are  small  oval  rods,  somewhat 
shorter  than  the  typhoid  bacillus  and  of  about  the 
same  thickness,  although  considerable  variation  in 
size  occurs.  The  rods  have  rounded  ends,  and  in 
staining,  the  middle  portion  is  usually  left  uncolored, 
giving  the  so-called  "polar-staining."  The  bacillus 
may  be  described  as  short,  oval,  capsulated,  non- 
motile,  non-spore-bearing,  and  polar-staining.  It 

grows  luxuriantly 
on  solidified  blood- 
serum  as  a  yellowish 

Fio.23.  — Bacillus  of  bubonic  plague,  show-     p.rav   Hpnosit     crrow- 
ing  polar-staining.  &ia\7 

ing     in     shred-like 

films  which  adhere  to  the  sides  or  drop  to  the  bot- 
tom of  the  culture  tube.  Growth  is  best  at  a 
temperature  between  36°  C.  and  39°  C.  (96.8°  F.- 
102.2°  F.).  It  is  destroyed  by  drying  at  room 
temperature  in  four  days;  by  exposure  to  sunlight 
in  four  hours;  by  moist  heat  at  100°  C.  (212°  F.) 
instantly,  and  at  80°  C.  (176°  F.)  in  five  minutes; 


BUBONIC   PLAGUE  139 

by  1  per  cent  carbolic  acid  in  ten  minutes;  and 
by  corrosive  sublimate  solution  1:1000  instantly. 

Plague  Infection  in  Man.  —  The  first  records  of 
plague  in  history  date  about  the  beginning  of  the 
Christian  era.  For  centuries  it  raged  in  Northern 
Africa,  and  during  the  middle  ages  extended  to 
Arabia,  India,  Asia  Minor,  and  throughout  Europe. 

History  relates  that  during  the  frightful  visitation 
of  plague  in  the  fourteenth  century  more  than  one 
fourth  of  the  population  of  Europe,  about  25,000,000 
people,  died,  ten  thousand  persons  dying  in  one  day 
in  Constantinople.  In  1664-1665  London  had  an 
epidemic  of  plague  which  carried  off  68,500  persons 
out  of  a  population  of  460,000. 

It  is  supposed  that  in  all  of  these  epidemics  other 
infections  were  present,  probably  malignant  typhus 
fever  and  " spotted  fever,"  both  of  which  are  favored 
by  the  same  unsanitary  conditions  that  are  so  great 
a  factor  in  epidemics  of  plague. 

Bubonic  plague  has  never  been  epidemic  in  Amer- 
ica, although  a  considerable  number  of  cases  have  oc- 
curred in  San  Francisco,  brought  by  ships  from  China; 
but  by  the  enforcement  of  quarantine  regulations 
and  medical  inspection  there  has  been  no  extended 
dissemination  of  the  disease. 

The  death  rates  in  different  epidemics  vary  from 


140  BACTERIOLOGY   FOR  NURSES 

50  per  cent  to  95  per  cent,  Yersin  reporting  the 
latter  after  the  Hong  Kong  epidemic  in  1894. 

Race  mortality  shows  also  a  wide  variation,  but  it 
is  attributed  rather  to  differences  in  social  condi- 
tions than  to  physical  differences  of  the  races.  At 
Hong  Kong  the  mortality  was  93.4  per  cent  among 
Chinese;  77  per  cent  among  Indians;  60  per  cent 
among  Japanese;  100  per  cent  among  Eurasians; 
and  only  18.2  per  cent  among  Europeans. 

There  are  two  forms  of  plague  in  man:  the  bubonic 
and  plague  pneumonia.  The  bubonic  form  often 
passes  into  a  septicaemic  form  when  the  bacilli  pass 
from  the  buboes  into  the  blood.  There  are  some- 
times subcutaneous  hemorrhages,  causing  dark 
spots,  from  which  the  name  "  black  death"  no  doubt 
originated.  In  plague  pneumonia,  which  is  much  less 
frequent  than  the  bubonic  type,  the  sputum  con- 
tains enormous  numbers  of  bacilli;  this  form  of 
plague  is  usually  fatal. 

Modes  of  Infection  and  Transmission.  —  Poverty 
and  filth  may  be  considered  the  two  greatest  con- 
tributing factors  in  the  continuance  and  spread  of 
plague.  In  the  middle  ages  the  hygienic  condition 
of  the  whole  world  was  identical  with  those  found  at 
present  in  China  and  India. 

The  " infectious  droplets"  from  the  pneumonic 


BUBONIC    PLAGUE  141 

plague  patient,  the  discharges  from  buboes,  and  the 
excreta  are  the  sources  of  infective  materials,  which 
must  find  entrance  to  the  body  through  breaks  in 
the  skin  or  mucous  membranes  to  produce  a  plague 
infection. 

The  usual  mode  of  infection  is  through  an  abrasion 
of  the  skin,  the  buboes  developing  in  the  neighbor- 
hood of  the  point  of  infection.  Infection  through 
the  tonsils  and  air-passages  may  occur,  but  pneu- 
monic plague  is  usually  secondary  to  the  infection  of 
other  tissues  through  abrasions. 

Infection  by  swallowing  is  not  supposed  to  occur. 
Aoyama  points  out  that  during  the  Hong  Kong 
epidemic  doctors  and  nurses  who  were  in  attendance 
upon  plague-infected  patients  were  rarely  infected; 
neither  were  three  hundred  English  soldiers  who  vol- 
unteered to  clean  and  disinfect  the  plague  pesthouses, 
which  is  strong  evidence  that  the  disease  is  not  con- 
tracted through  the  alimentary  tract  and  rarely 
through  the  air-passages. 

It  was  long  observed  in  many  epidemics  that 
transmission  and  infection  did  not  always  occur, 
even  when  healthy  persons,  such  as  doctors  and 
nurses,  were  brought  into  close  contact  with  plague- 
infected  patients. 

It  was  also  noted  that  epidemics  of  plague  were 


142  BACTERIOLOGY    FOR   NURSES 

often  if  not  always  accompanied  by  great  mortality 
among  rats,  and  investigation  proved  that  the  plague' 
of  rats  and  the  plague  of  man  were  both  due  to  B. 
pestis,  some  writers  believing  that  plague  is  prima- 
rily a  disease  of  rats  and  contracted  from  them  by 
men.  This  theory  led  to  much  study  of  the  methods 
whereby  the  infection  is  transferred  to  man.  As  the 
infection  does  not  take  place  through  the  alimentary 
tract,  it  could  not  be  carried  by  food  or  utensils 
which  had  been  contaminated  by  rats,  neither  was  it 
possible  for  every  infected  person  to  have  come  into 
direct  contact  with  rats:  but  it  was  discovered  that 
fleas  taken  from  the  bodies  of  plague-infected  rats, 
or  from  rats  in  an  infected  house,  and  transferred  to 
the  bodies  of  healthy  rats,  would  transmit  plague  to 
the  latter. 

The  Advisory  Committee  of  the  Indian  Plague 
Commission,  in  1905,  by  a  series  of  experiments, 
proved  conclusively  that  rat  fleas  carried  plague  to 
healthy  animals  and  to  man. 

The  following  are  some  of  the  experiments  which  were 
conducted.  A  series  of  six  huts  were  built  which  only 
differed  in  the  structure  of  their  roofs.  In  two  the  roofs 
were  made  of  ordinary  native  tiles,  in  which  rats  freely 
lodge;  in  two  others  flat  tiles  were  used,  in  which  rats 
live,  but  in  which  they  have  not  such  facilities  for  move- 


BUBONIC    PLAGUE  143 

ment  as  in  the  first  set,  and  in  the  third  pair  the  roof  was 
formed  of  corrugated  iron.  Under  the  roof  in  each  case 
was  placed  a  wire  diaphragm,  which  prevented  rats  or  their 
droppings  having  access  to  the  hut,  but  which  would  not 
prevent  fleas  falling  down  on  to  the  floor  of  the  hut.  The 
huts  were  left  a  sufficient  time  to  become  infected  with 
rats,  and  then  on  the  floor  in  each  case  healthy  guinea- 
pigs  artificially  infected  with  plague  were  allowed  to  run 
about  together.  In  the  first  two  sets  of  huts  to  which 
fleas  had  access  the  healthy  guinea-pigs  contracted  plague, 
while  in  the  third  set  they  remained  unaffected,  though 
they  were  freely  liable  to  contamination  by  contact  with 
the  bodies  and  excreta  of  the  diseased  animals.  In  the 
third  set  of  huts  no  infection  took  place  as  long  as  fleas 
were  excluded,  but  when  accidentally  these  insects  obtained 
admission,  then  infection  of  the  uninoculated  animals 
commenced.  Other  experiments  were  also  performed. 
In  one  case  healthy  guinea-pigs  were  suspended  in  a  cage 
two  inches  above  a  floor  on  which  infected  and  flea- 
infested  animals  were  running  about.  Infection  occurred 
in  the  cage,  but  if  the  latter  were  suspended  at  a  distance 
above  the  floor  higher  than  a  flea  could  jump,  then  no 
infection  took  place.  Again,  in  a  hut  in  which  guinea- 
pigs  had  died  of  plague,  and  which  contained  infected 
fleas,  two  cages  were  placed,  each  containing  a  monkey. 
One  cage  was  surrounded  by  a  zone  of  sticky  material 
broader  than  the  jump  of  a  flea.  The  monkey  in  this 
cage  remained  unaffected,  but  the  other  monkey  con- 
tracted plague.  (Muir  and  Ritchie.) 


144  BACTERIOLOGY   FOR   NURSES 

These  experiments  suggest  practical  measures  for 
the  control  of  plague.  Rats,  fleas,  and  filth  being 
closely  connected,  it  remains  for  those  concerned 
to  remove  these  causes.  Such  measures  may  be 
easily  employed  in  Europe  and  America,  but  in  China 
and  India,  whose  inhabitants  live  in  unspeakable 
filth,  it  will  require  generations  of  education  to  re- 
move the  conditions  which  so  strongly  favor  the 
development  and  spread  of  the  disease. 

Plague  in  Animals.  —  Rats,  mice,  guinea  pigs, 
and  ground  squirrels  are  very  susceptible  to  plague, 
and  monkeys  are  particularly  sensitive  to  artificial 
inoculation.  Rats  and  guinea  pigs  may  be  infected 
by  feeding.  Dogs,  swine,  cattle,  and  horses  may  be 
inoculated  artificially,  but  do  not  contract  the  disease 
under  natural  conditions. 

As  before  stated,  the  plague  of  rats  has  been  the 
subject  of  widespread  investigations,  which  have 
led  some  observers  to  declare  that  plague  is  primarily 
a  disease  of  rats,  not  man. 

Protective  and  Curative  Sera.  —  "Haffkine's 
prophylactic"  serum  has  been  used  as  a  preventive 
of  plague  in  India  to  a  considerable  extent  and 
degree  of  success. 

The  statistics  of  Punjab  in  1902  report  that  among 
the  inoculated  1.8  per  cent  became  infected,  while 


BUBONIC   PLAGUE  145 

7.7  per  cent  of  the  uninoculated  contracted  the  dis- 
ease; while  the  deaths  among  the  inoculated  were  23.9 
per  cent,  and  among  the  uninoculated  60.1  per  cent. 

The  Yersin  anti-plague  serum  is  used  for  curative 
purposes  with  fairly  good  results. 

Prophylaxis. — Besides  the  use  of  Haffkine's  prophy- 
lactic serum  against  plague  infection,  the  exclusion 
of  rats,  mice,  and  domestic  pets  which  may  harbor 
rat  fleas,  and  the  practice  of  scrupulous  cleanliness 
both  inside  and  outside  the  house,  are  the  best 
preventive  measures  to  be  employed  for  the  protec- 
tion of  a  household.  The  fumigation  with  sulphur 
or  formaldehyde  of  the  cellar  and  basement,  followed 
by  a  liberal  application  of  whitewash  to  the  ceilings, 
walls,  and  floors,  is  recommended  for  driving  away 
rats  and  killing  fleas. 

It  was  formerly  thought  that  the  poorer  classes  in 
China  and  India  usually  contracted  plague  through 
abrasions  on  the  feet,  as  they  never  wear  shoes,  but 
in  the  light  of  the  knowledge  of  fleas  as  carriers  of 
the  plague  bacillus,  it  is  likely  that  the  bare  feet  are 
more  often  bitten  by  fleas  in  the  soil,  in  which  they 
are  found  in  large  numbers.  That  the  soil  becomes 
infected  in  all  epidemics  of  plague  there  is  no  doubt, 
and  attempts  are  made  to  disinfect  the  soil  by  cover- 
ing it  in  the  immediate  vicinity  of  dwellings  with 


146  BACTERIOLOGY   FOR   NURSES 

freshly  made  whitewash,  which  will  destroy  both 
fleas  and  infective  materials. 

When  a  member  of  a  household  contracts  plague, 
it  is  customary  to  remove  the  patient  to  an  isolation 
hospital  at  once,  and  to  quarantine  the  house  and  its 
remaining  members  for  ten  or  twelve  days,  at  the 
same  time  cleaning  and  disinfecting  the  house  and 
its  contents  to  the  minutest  crevice. 

Patients  recovering  from  plague  are  kept  in  quar- 
antine for  four  or  six  weeks  after  convalescence 
begins,  as  the  bacilli  are  often  found  as  late  as  three 
weeks  after  the  beginning  of  convalescence. 

In  carrying  out  prophylactic  measures  against 
all  infectious  diseases  the  sources  and  modes  of 
infection  should  be  kept  constantly  in  mind  to  serve 
as  a  guide. 


CHAPTER  XIV 

ASIATIC   CHOLERA.      RELAPSING   FEVER 

ASIATIC  Cholera  is  an  acute  infectious  disease 
characterized  by  great  intestinal  irritation  accom- 
panied by  profuse  watery  discharges  called  "  rice- 
water  "  discharges,  and  by  vomiting.  The  general 
symptoms  include  profound  prostration,  cold, 
clammy  skin,  cardiac  depression,  cramps  of  the 
muscles,  and  suppression  of  urine.  Cholera  is  due 
to  the  Spirillum  cholerce,  which  was  discovered  and 
described  first  by  Koch  during  his  investigations  of 
cholera  in  Egypt  in  1883. 

Prior  to  this  time  little  or  nothing  was  known  of 
the  cause  of  cholera,  although  the  disease  existed 
for  centuries  in  India,  and  since  1831  had  been 
epidemic  at  times  in  all  parts  of  Europe.  In  the 
United  States  cholera  has  been  epidemic  at  eight 
different  times  between  1832  and  1873. 

147 


148  BACTERIOLOGY   FOR   NURSES 

Cholera  spirilla  are  short,  slightly  curved  rods 

having  the  general  appearance  of   a  comma  and 

sometimes    called    "  comma    bacillus."    The    rods 

^        usually  occur  singly,  but  may  appear  in 

O"^J^    pairs,  curving  in  an  opposite  direction 

J?V^  f     like  the   letter   s.      Longer  forms   fre- 

'**"       quently   develop    in    cultures,   but    are 

Spirilla  of  Asi-  rarely  found  in  the   intestines.     They 

are    actively    motile,    having    a    single 

flagellum   at   one   end   only.     They   do   not   form 

spores,  and  stain  readily  with  aniline  dyes,  losing 

their  color  in  Gram's  method. 

The  spirilla  grow  readily  on  all  ordinary  media. 
An  alkaline  reaction  is  necessary  for  all  media,  the 
spirilla  being  extremely  sensitive  to  the  action  of 
acids. 

At  the  end  of  twenty-four  hours  the  colonies 
become  visible  to  the  naked  eye,  showing  a  round, 
even  contour,  which  later  becomes  irregular,  and  a 
granular  surface.  At  the  end  of  forty-eight  hours 
liquefaction  of  the  gelatin  occurs,  resulting  in 
a  characteristic  funnel-shaped  depression  in  the 
colony. 

Cholera  spirilla  are  strictly  aerobic  organisms; 
they  possess  no  great  powers  of  resistance,  being 
quickly  killed  by  drying,  by  chemical  disinfectants, 


ASIATIC   CHOLERA  '     149 

and  by  60°  C.  (140°  F.)  in  ten  minutes ;  neither  do 
they  retain  their  vitality  for  any  length  of  time  in 
soil  or  water.  They  may  retain  their  vitality  for 
several  days  upon  the  surface  of  fruit  and  vege- 
tables, if  kept  in  a  cool,  moist  place.  Whether 
there  is  any  multiplication  of  cholera  spirilla  in  im- 
pure water  is  still  a  matter  of  doubt,  although  there 
can  be  no  doubt  that  they  retain  their  vitality  in 
impure  water  for  several  days,  as  cholera-infected 
drinking  water  is  the  usual  source  of  infection. 

Cholera  Infection  in  Man.  — The  proof  of  the  con- 
nection of  the  cholera  spirillum  with  Asiatic  cholera 
in  man  has  been  demonstrated  several  times  in 
laboratory  workers  who  by  accident  or  design  have 
become  infected  by  the  materials  with  which  they 
were  working;  all  of  these  instances  occurring  when 
no  cholera  existed  in  the  country. 

The  spirilla  are  found  in  the  intestines,  but  do  not 
enter  the  blood  or  internal  organs.  The  small  intes- 
tines are  mostly  affected,  the  epithelium  being  shed, 
and  the  characteristic  " rice-water"  discharges  con- 
taining enormous  numbers  of  spirilla,  almost  pure 
cultures.  Like  typhoid  fever,  cholera  is  contracted 
largely  through  polluted  drinking  water,  i.e.  the 
spirilla  must  enter  the  alimentary  tract,  and  in- 
fected drinking  water  is  the  common  source.  Un- 


150  BACTERIOLOGY   FOR   NURSES 

cooked  food,  particularly  milk,  or  food  which  lias 
been  exposed,  may  be  infected  by  flies  which  carry 
the  organisms  upon  their  feet  or  bodies  from  sewers, 
privies,  and  neglected  cholera  discharges.  Dishes  and 
table  linen  may  also  be  infected  in  the  same  way. 
The  cholera  spirilla  leave  the  body  only  in  the  feces, 
and  it  has  been  demonstrated  that  the  fecal  dis- 
charges of  perfectly  healthy  persons  living  in  a 
cholera-infected  district  may  also  contain  large 
numbers  of  spirilla,  which  is  a  conclusive  argument 
in  the  reasons  for  disinfecting  all  bowel  discharges 
and  linen  soiled  with  fecal  matter,  and  for  sterilizing 
the  drinking  water.  The  nursing  methods  for  the 
prevention  of  infection  in  cholera  are  identical 
with  those  in  typhoid  fever. 

The  period  of  incubation  being  short,  cholera 
epidemics  are  explosive  in  their  suddenness.  The 
last  epidemic  of  cholera  in  Europe  occurred  in 
Hamburg  in  1892  and  was  a  clinical  demonstra- 
tion of  an  epidemic  caused  by  infected  drinking 
water.  Hamburg  and  Altona  are  practically  one 
city,  although  under  two  distinct  municipal  govern- 
ments. Both  cities  obtained  water  from  the  river 
Elbe,  but  in  Altona  the  city  water  supply  was  filtered, 
and  in  Hamburg  it  was  not  at  that  time,  which  re- 
sulted in  Hamburg  having  16,957  cases  of  cholera, 


ASIATIC   CHOLERA  151 

with  8606  deaths,  while  Altona  during  the  same 
period  had  516  cases,  most  of  them  having  been  in- 
fected while  working  in  Hamburg,  with  316  deaths. 

Since  this  epidemic  Hamburg  has  established  a 
satisfactory  system  of  filtration;  and  though  there 
has  been  no  opportunity  for  proving  its  value  in 
times  of  cholera,  the  death  rate  from  typhoid  fever 
has  fallen  from  34  per  100,000  to  6  per  100,000. 

Cholera  in  Animals.  —  Under  natural  conditions 
animals  do  not  contract  cholera.  Rabbits  have 
been  successfully  inoculated  by  injection  into  the 
ear  vein,  and  young  rabbits  have  been  infected 
through  spirilla  being  placed  upon  the  teats  of  the 
mother. 

Intraperitoneal  injections  into  guinea-pigs  has 
also  produced  cholera,  this  method  being  often 
employed  to  test  the  virulence  of  cholera  cultures. 

Toxins.  —  For  a  long  time  there  was  no  evidence 
that  cholera  spirilla  produced  toxins,  as  do  the  teta- 
nus and  diphtheria  bacilli,  and  it  was  supposed  that 
the  cholera  spirilla  contained  only  an  endotoxin, 
that  is,  a  poison  within  the  organism;  but  later 
investigations  of  Metchnikoff,  Roux,  and  others 
proved  that  toxins  are  produced,  and  that  the 
serum  of  actively  immunized  animals  does  contain  an 
antitoxin  which  neutralizes  the  cholera  toxin. 


152  BACTERIOLOGY   FOR  NURSES 

Prophylaxis.  —  Vaccination  against  cholera  has 
been  successfully  practiced  in  India  for  some  years. 
Guinea-pigs  are  immunized  by  repeated  intraperito- 
neal  injections  of  small  doses  of  spirilla  until  a  high 
degree  of  immunity  is  attained.  If  the  blood- 
serum  from  the  immunized  guinea-pig  be  injected, 
with  a  fatal  dose  of  the  virulent  spirilla,  into  a  suscep- 
tible guinea-pig,  it  is  found  that  a  small  dose  of  the 
immune  blood-serum  will  protect  the  susceptible 
animal  against  a  ten  times  fatal  dose  of  virulent 
spirilla.  The  immunized  blood-serum  dissolves  (bac- 
teriolysis) the  spirilla,  the  phenomenon  being  known 
as  "Pfeiffer's  reaction."  The  blood-serum  of  an 
immunized  animal  has  also  an  agglutinative  action 
against  the  cholera  spirilla,  analogous  to  Widal's 
reaction  in  typhoid  fever. 

Haffkine's  vaccination  against  cholera,  which  is 
employed  so  extensively  in  India,  is  carried  out  in 
accordance  with  these  principles  and  has  proved  to  be 
successful. 

Powell  gives  the  following  statistics :  — 

NUMBER  CASES  DEATHS 

Unvaccinated        6549  198  124 

Vaccinated  5778  27  14 

Besides  vaccination  for  the  prevention  of  cholera, 
the  careful  observance  of  quarantine,  particularly 


ASIATIC   CHOLERA  153 

of  ships  or  trains  coming  from  infected  countries  or 
districts,  is  of  the  greatest  importance  in  preventing 
the  spread  of  the  disease. 

When  a  community  is  threatened  with  an  invasion 
of  cholera,  the  water,  milk,  and  other  food  supplies, 
as  well  as  the  dishes,  should  be  freshly  sterilized  be- 
fore each  meal.  No  uncooked  food  should  be  used, 
and  all  food,  dishes,  dish  towels,  and  table  linen 
should  be  protected  from  flies  and  other  insects. 

All  persons  suffering  from  diarrhoea,  no  matter 
how  mild  the  form,  should  be  isolated,  and  the  bowel 
discharges  be  disinfected  with  the  same  care  as 
would  be  observed  in  a  typical  case  of  cholera. 

As  in  typhoid  fever  the  mild  cases  of  cholera  who  are 
not  confined  to  their  beds  are  of  more  danger  to  a 
community  than  those  who  are  violently  ill,  because 
in  the  mild  cases  it  is  thought  unnecessary  to  disin- 
fect the  fecal  discharges  and  the  water-closets,  and 
many  fatal  cases  owe  their  origin  to  this  neglect. 

The  details  of  nursing  cholera  patients,  as  before 
stated,  are  identical  with  those  of  typhoid  fever. 
The  disinfection  of  excreta  and  clothing  soiled  with 
excreta  is  especially  important ;  the  dishes  used  by 
the  patient  should  be  boiled  after  each  meal,  and 
refuse  food  should  be  burned. 

Cholera  patients  are  not  released  from  quarantine 


154  BACTERIOLOGY   FOB   NURSES 

until  bacteriological  examinations  show  that  the 
fecal  discharges  are  free  from  cholera  spirilla. 

Allied  Spirilla.  —  A  number  of  spirilla  strongly 
resembling  S.  cholera  have  been  observed  in  sewage 
and  impure  water  especially,  most  of  which  seem 
to  be  saprophytes. 

RELAPSING   FEVER 

Relapsing  fever,  as  the  name  indicates,  is  a  fever 
characterized  by  a  number  of  seizures,  or  relapses, 
which  occur  from  two  to  four  or  more  times.  The 
disease  is  due  to  Spirillum  obermeieri,  which  was 
first  observed  by  Obermeier  in  1873  in  the  blood 
of  patients  suffering  with  relapsing  fever. 

The  disease  has  at  times  prevailed  in  all  parts  of 
Europe,  India,  and  the  United  States;  but  in  recent 
years  the  disease  rarely  occurs  in  the  United  States. 

S.  obermeieri  is  a  large  spirillum  with  several 
spirals  and  a  single  flagellum  at  one  end.  It  is  ac- 
tively motile.  All  attempts  at  artificial  cultivation 
have  so  far  proved  unsuccessful. 

Infection  occurs  through  inoculation;  and  mon- 
keys, rats,  and  mice  may  also  be  infected.  The 
disease  is  rarely  fatal  in  man  or  animals.  There  are 
several  diseases  caused  by  similar  organisms,  the 
principal  one  being  African  tick  fever,  in  which  man 
is  infected  by  means  of  a  tick  bite. 


CHAPTER  XV 

DISEASES    DUE   TO    PROTOZOA 
AMCEBIC  DYSENTERY,  MALARIAL  FEVER 

BESIDES  the  infectious  diseases  due  to  the  smallest 
form  of  vegetable  life  which  we  know  as  bacteria, 
there  are  several  widespread  diseases  in  both  men 
and  animals  which  are  caused  by  animal  micro- 
organisms, known  as  pathogenic  protozoa  (sing,  pro- 
tozoori), 

Protozoa  are  the  smallest  form  of  animal  life,  and 
like  bacteria,  are  unicellular  and  of  many  species, 
varying  in  size,  shape,  and  methods  of  reproduction. 

In  some  species  of  protozoa  the  life  cycle  is  as  simple 
as  that  of  bacteria,  while  in  others  it  is  extremely 
complex.  A  large  number  are  parasitic  upon  ani- 
mals and  plants,  and  by  their  invasions  into  the 
bodies  of  men  and  animals  are  the  cause  of  many 
serious  maladies,  especially  in  the  tropics. 

A  class  of  protozoan  parasites  known  as  Sporozoa 
are  nearly  as  widely  distributed  as  bacteria. 

165 


156  BACTERIOLOGY   FOR   NURSES 

AAKEBIC  DYSENTERY 

Dysentery  is  a  term  used  to  designate  an  inflamma- 
tion of  the  colon,  accompanied  by  excessive  diarrhoea ; 
but  dysentery  occurs  in  several  distinct  forms  which 
are  due  to  different  organisms.  Thus,  several  forms 
of  dysentery  are  due  to  bacteria  —  Bacillus  dysen- 
teries —  of  which  there  are  two  or  three  varieties, 
in  other  words  are  due  to  vegetable  organisms  (bac- 
teria) ;  while  amcebic  dysentery,  a  chronic  form  usually 
occurring  in  the  tropics,  is  caused  by  a  protozoon 
known  as  entamceba  histolytica.  In  amcebic  dysentery 
large  numbers  of  amoebae  are  found  in  the  intestinal 
walls,  which  they  penetrate,  causing  characteristic 
ulcerations.  The  colon  and  rectum  are  most  affected, 
although  the  internal  organs,  notably  the  liver,  are 
frequently  invaded,  resulting  in  large  abscesses  of  the 
liver. 

The  amoebae  of  dysentery  average  about  30 /A  in 
diameter,  are  actively  motile,  and  multiply  by  spore- 
formation.  They  possess  protrusions  for  locomotion 
—  pseudopodia  —  which  they  use  to  penetrate  the 
mucous  membranes. 

Artificial  cultivation  of  the  amoebae  of  dysentery 
has  been  attended  with  great  difficulties,  and  has 
been  successful  only  by  the  use  of  elaborate  special 
methods. 


AMCEBIC   DYSENTERY  157 

It  is  not  known  definitely  how  nor  where  the 
amoeba  of  dysentery  multiply  outside  of  the  body, 
although  raw  foods  and  water  carry  the  organisms. 
It  is  said  that  the  sand  nitration  of  water  which 
effectually  removes  the  typhoid  and  cholera  organ- 
isms does  not  withhold  dysentery  amoebae.  Mon- 
keys in  confinement  contract  amoebic  dysentery 
by  natural  conditions,  and  cats  and  other  animals 
have  been  infected  by  introducing  the  amoebae  into 
the  rectum,  and  by  feeding  them  the  spores. 

Amcebse  are  found  in  the  intestines  of  healthy 
persons  which  are  called  entamceba  coli;  these  mul- 
tiply by  both  fission  and  spore-formation,  and  are 
considered  an  entirely  distinct  species. 

A  class  of  protozoa  known  as  trypanosomes  cause 
a  number  of  diseases  common  to  horses,  cattle,  and 
wild  animals  in  South  Africa,  as  well  as  the  terrible 
"sleeping  sickness"  among  human  beings. 

Transmission  takes  place  through  the  bites  of 
insects:  rat  fleas,  lice,  ticks,  and  the  " tsetse-fly" 
which  carries  the  infection  of  "sleeping  sickness." 
It  is  believed  that  the  parasites  —  trypanosomes  — 
exist  in  the  bodies  of  the  larger  wild  animals,  and  are 
always  transmitted  to  man  and  the  domestic  animals 
by  the  bites  of  flies  or  other  insects. 


158  BACTERIOLOGY   FOR   NURSES 

MALARIAL  FEVER 

Malarial  fevers  are  characterized  by  periodic  oc- 
currences of  chills,  fever,  and  sweating,  with  a  dis- 
appearance of  the  symptoms  between  the  paroxysms. 
The  intermission  varies,  occurring  daily  —  quotidian; 
every  other  day  —  tertian;  and  with  an  interval  of 
two  days  —  quartan.  Of  the  four  forms  of  malarial 
fever,  one,  the  " pernicious"  type,  is  usually  fatal 
and  seldom  occurs  outside  of  tropical  countries. 
Malarial  fever  is  due  to  a  parasite  known  as  plas- 
modium  malaria,  or  more  properly  hemamceba.  The 
parasite  of  malaria  was  first  observed  and  described 
by  Leverari,  a  French  army  surgeon  in  Algiers,  in 
1880.  Shortly  after,  Golgi  observed  that  the  several 
types  of  malaria  were  due  to  different  malarial 
organisms,  and  that  the  chill  always  occurred  when 
sporulation  took  place;  that  is,  when  a  brood  of 
young  parasites  entered  the  blood.  The  parasite 
attaches  itself  to  the  red  corpuscles  of  man  and 
there  passes  through  the  process  of  spore-formation, 
the  duration  of  the  process  corresponding  to  the 
intermission  between  the  paroxysms. 

Before  these  discoveries  the  cause  of  malaria  had 
been  attributed  to  low  marshy  lands,  to  the  rainfall, 
to  prevailing  winds,  to  the  season,  and  to  the  drink- 


MALARIAL    FEVER  159 

ing  water;  but  following  the  work  of  Leveran  and 
Golgi  a  great  amount  of  research  was  directed  to  find- 
ing the  mode  of  infection. 

It  was  at  first  thought  that  the  parasite  existed  in 
the  soil  and  water;  but  all  attempts  to  reproduce 
the  disease  through  the  alimentary  tract  or  through 
wounds  of  the  skin  by  means  of  soil  and  water  were 
unsuccessful. 

This  investigation  continued  for  several  years  until 
1897,  when  Ronald  Ross,  an  English  army  surgeon  in 
India,  found  that  malarial  infection  can  occur  only 
through  the  bite  of  a  certain  mosquito  (Anopheles), 
and  that  the  parasite  of  malaria  passes  through  an 
extraordinary  life  cycle  in  which  the  mosquito  is  the 
definitive  host  and  man  the  intermediate  host.  The 
manner  in  which  the  mosquito  acquires  the  parasite 
and  conveys  it  to  man  is  briefly  as  follows:  On 
sucking  the  blood  of  a  malarial  subject  the  parasite 
is  taken  into  the  stomach  and  intestines  of  the  insect. 
It  passes  thence  to  the  salivary  glands,  where  it 
remains  until  the  mosquito  bites  again,  when  through 
the  muscular  effort  of  sucking  blood  the  parasite  is 
readily  injected  into  the  tissues  of  the  person  on 
whom  the  insect  is  feeding.  (Abbott.) 

From  these  discoveries  the  former  reasons  assigned 
as  causes  of  the  disease  were  easily  explained,  viz. 


160  BACTERIOLOGY    FOR    NURSES 

marshy  lands,  rainfall,  polluted  water,  season,  and 
prevailing  winds.  Mosquitoes  breed  in  marshy 
places  where  the  amount  of  moisture  would  vary  with 
the  rainfall ;  their  time  of  breeding  and  development 
coincides  with  the  malarial  season;  and  they  are 
carried  considerable  distances  by  the  wind. 

Prophylaxis.  —  For  generations  malarial  fevers 
have  been  combated  with  repeated  doses  of  quinine, 
which  is  injurious  and  destructive  to  the  young 
parasites  of  malaria.  For  this  reason  the  quinine  is 
given  when  the  fever  is  declining,  which  is  soon  after 
the  young  broods  enter  the  blood.  Persons  suffering 
from  malarial  fever  should  be  shielded  from  further 
mosquito  bites,  as  the  insects  can  only  become  in- 
fected by  sucking  the  blood  of  the  malarial  patient, 
and  if  there  are  no  infected  mosquitoes  there  will 
be  no  malarial  infection  for  other  persons. 

The  draining  of  lowlands  and  the  application  of 
kerosene  to  standing  water  has  rid  many  localities  of 
malaria  by  destroying  the  breeding  places  of  mos- 
quitoes; but  the  expense  of  such  procedures  is  great, 
and  consequently  not  always  practical. 

The  screening  of  houses  is  one  of  the  most  effectual 
methods  of  preventing  malarial  fevers.  This  way 
shields  the  person  suffering  with  the  disease  from 
further  bites,  and  as  the  Anopheles  is  not  active  until 


MALARIAL    FEVER  161 

sundown,  the  occupants  of  a  well-screened  house  are 
comparatively  safe  from  infection. 

Among  the  many  extremely  interesting  experi- 
ments carried  on  to  demonstrate  the  proof  that  the 
Anopheles  is  the  host  of  the  parasite  of  malaria  were 
those  of  the  English  doctors  who  lived  for  months 
on  the  Roman  Campagna,  where  malaria  has  raged 
for  centuries.  These  men  occupied  a  mosquito-proof 
house,  and  while  they  drank  the  same  water  and 
mixed  freely  with  many  natives  who  were  suffering 
from  the  disease,  they  did  not  contract  it. 

Another  interesting  experiment  was  made  by 
sending  mosquitoes  which  had  bitten  malarial 
patients,  from  Italy  to  England,  where  Dr.  Manson 
permitted  himself  to  be  bitten  by  them  and  con- 
tracted a  typical  attack  of  malarial  fever. 


CHAPTER  XVI 

INFECTIOUS   DISEASES    OF   UNKNOWN    CAUSE 

SMALLPOX  (VARIOLA),  HYDROPHOBIA  (RABIES),  SCARLET 
FEVER,  MEASLES,  WHOOPING  COUGH,  MUMPS,  YELLOW 
FEVER,  TYPHUS  FEVER,  ROCKY  MOUNTAIN  SPOTTED 
FEVER,  EPIDEMIC  INFANTILE  PARALYSIS. 

AMONG  the  common  transmissible  diseases  are  a 
number  which  have  been  the  subjects  of  research 
and  experiment  continuously  since  the  founding  of 
the  science  of  bacteriology,  but  which  yet  must 
be  listed  as  of  unknown  origin. 

SMALLPOX,  OR  VARIOLA 

Smallpox  is  an  acute,  infectious,  highly  conta- 
gious, eruptive  disease.  The  eruption  passes  through 
three  stages,  (1)  papular,  (2)  vesicular,  and  (3) 
pustular,  and  finally  heals  with  a  scab.  Like  most 
eruptive  diseases,  smallpox  is  especially  contagious 
during  the  period  of  desquamation.  Several  micro- 
organisms, have  been  found  in  the  lesions  of  small- 
pox, but  none  have  been  proved  to  be  the  cause  of 
the  disease. 

162 


SMALLPOX  163 

The  pyogenic  bacteria  are  nearly  always  found  in 
the  pustules  of  smallpox,  and  it  is  said  that  when  the 
secondary  infection  is  due  to  streptococci,  the  attack 
is  nearly  always  fatal. 

Smallpox  is  common  to  all  ages,  but  by  far  the 
greatest  number  of  deaths  occur  among  young  per- 
sons. The  colored  races  are  more  susceptible  to 
smallpox  than  the  whites. 

Historical  medical  records  relate  the  existence  of 
smallpox  in  Central  Asia  during  the  tenth  century, 
in  Europe  during  the  twelfth  century,  and  that  it 
was  introduced  into  North  America  by  the  Spaniards 
in  the  sixteenth  century. 

Transmission.  —  The  modes  of  infection  in  small- 
pox, like  the  microorganism  which  causes  it,  are 
still  questions  to  be  answered;  for  years  it  was 
thought  the  transmission  was  through  the  air, 
and  of  course  by  contact,  but  the  air-borne  theory- 
is  now  questioned  by  some  of  the  best  authori- 
ties, and  no  new  light  has  been  thrown  on  the 
subject. 

Prophylaxis.  —  For  the  prevention  of  smallpox 
vaccination  is  by  far  the  most  important  measure 
to  be  employed ;  without  vaccination,  isolation  and 
disinfection  can  be  of  limited  effect. 

Prior  to  Jenner's  discovery  of  the  value  of  the  virus 


164  BACTERIOLOGY   FOR   NURSES 

of  cowpox  (vaccina),  inoculation  had  been  prac- 
ticed. It  had  been  found  that  inoculation  by  scarify- 
ing the  skin  and  introducing  a  small  amount  of  virus 
from  a  smallpox  pustule  would  usually  result  in  a 
mild  attack  of  smallpox,  with  immunity  from  the 
disease  in  the  future;  but  this  form  of  the  disease 
was  as  contagious  as  smallpox  contracted  in  the 
usual  way,  and  not  infrequently  was  of  a  serious,  if 
not  fatal,  type. 

In  1798  Jenner  published  an  account  of  his  dis- 
covery that  vaccination  with  the  virus  of  cow- 
pox  produced  only  a  slight  local  infection  and 
conferred  immunity  from  smallpox.  Jenner  had 
observed  that  milkers  were  often  infected  through 
abrasions  upon  the  hands  by  the  pustules  of  cow- 
pox  upon  the  cow's  teats,  and  that  they  were  hence- 
forth immune  from  smallpox.  The  fact  that  vacci- 
nation not  only  conferred  immunity  for  several  years, 
but  that  the  general  symptoms  produced  were  of  the 
mildest  character  and  non-contagious,  led  to  its 
adoption  in  all  civilized  countries,  which  has  resulted 
in  stamping  out  the  frightful  epidemics  of  smallpox 
which  were  formerly  common  occurrences. 

Vaccination  should  always  be  done  under  the 
strictest  aseptic  conditions:  that  serious  secondary 
infections  have  often  occurred  through  vaccination 


RABIES  165 

cannot  be  denied,  and  so  long  as  these  occur  there 
will  always  be  violent  objectors  to  all  vaccination 
among  the  ignorant  who  neither  understand  the 
principle  of  immunity  nor  the  possibilities  of  second- 
ary infection. 

The  relation  of  smallpox  (variola)  to  cowpox  (vac- 
cina)  is  still  a  subject  for  controversy,  having  raged 
without  ceasing  since  Jenner's  discovery  in  1798. 

At  the  present  time  the  supply  of  vaccine  is  ob- 
tained by  the  continuous  inoculation  of  calves, 
which  are  kept  at  the  vaccine  laboratories  for  that 
purpose. 

RABIES,  OR  HYDROPHOBIA 

Rabies,  or  hydrophobia,  is  an  infectious  disease 
which  is  communicated  from  one  animal  to  another 
or  to  man  by  a  bite.  The  name  hydrophobia  (fear  of 
water)  is  a  misnomer,  as  the  subjects  suffer  no  fear 
of  water,  but  have  a  dread  of  the  act  of  swallow- 
ing anything,  which  causes  severe  spasms  of  the 
muscles  of  the  throat. 

All  attempts  to  discover  the  organism  contained 
in  the  virus  of  hydrophobia  have  so  far  been  fruitless. 
That  the  disease  is  caused  by  a  microorganism 
seems  to  be  accepted  as  a  fact,  as  there  are  many 
points  of  resemblance  between  the  infection  of  rabies 


166  BACTERIOLOGY    FOR    NURSES 

and  some  of  the  bacterial  diseases,  notably  tetanus. 
Pasteur's  protective  inoculation  serum  is  also  re- 
garded as  another  proof  that  hydrophobia  is  due  to  a 
specific  microorganism,  which  is  too  small  to  be  seen 
with  a  microscope  (ultra-microscopic). 

In  the  rabid  animal  and  in  man  the  virus  is 
contained  in  the  saliva.  Infection  occurs  through 
the  bite,  bites  upon  an  exposed  surface  such  as 
the  face  and  hands  being  usually  much  more 
serious  than  when  the  skin  is  covered  by  the 
clothing ;  in  the  latter  case  the  clothing  holds 
back  the  saliva.  Infection  may  also  be  carried 
by  the  licking  of  an  abraded  surface  by  a  rabid 
animal. 

Hydrophobia  occurs  epidemically  among  wolves, 
dogs,  sheep,  cattle,  and  horses;  but  wolves  and  dogs 
are  the  most  susceptible. 

There  are  two  forms  of  hydrophobia:  (1)  furious 
rabies,  characterized  by  restlessness,  and  (2)  dumb  or 
paralytic  rabies. 

In  animals  the  period  of  incubation  is  from  three 
to  six  weeks,  the  first  symptoms  being  restlessness, 
snapping,  and  tearing  at  all  objects  or  persons,  a 
peculiar  change  in  the  tone  of  voice,  followed  by 
spasms  of  the  throat  muscles  upon  attempts  at 
swallowing,  with  an  abundance  of  saliva.  General 


RABIES  167 

convulsions  and  paralysis  are  speedily  followed  by 
death. 

In  man  the  period  of  incubation  is  from  two  weeks 
to  six  months  or  more,  the  average  period  being  forty 
days.  The  initial  symptoms  in  man  are  pain  near 
the  site  of  infection,  with  great  nervous  irritability, 
followed  by  the  characteristic  spasms  of  the  throat 
muscles,  delirium,  general  convulsions,  paralysis, 
and  death,  the  duration  of  the  disease  being  usu- 
ally from  four  to  eight  days. 

Prophylaxis.  —  Prior  to  1885  the  only  treatment 
given  to  persons  who  had  been  bitten  by  rabid  animals 
was  the  cauterization  and  ordinary  surgical  care  of 
the  wounds;  but  Pasteur  at  this  time  made  public 
the  results  of  his  great  work  in  discovering  a  protec- 
tive inoculation  serum  against  hydrophobia.  His 
experiments  were  a  brilliant  success,  and  have  re- 
sulted in  the  establishment  of  Pasteur  Institutes  for 
the  treatment  of  hydrophobia  in  all  parts  of  the 
world. 

The  success  of  the  treatment  or  immunization  de- 
pends largely  upon  the  time  which  elapses  between 
the  bite  and  the  beginning  of  the  treatment.  It  is 
now  customary  to  send  persons  who  have  been  bitten 
by  rabid  animals  with  all  possible  speed  to  the 
nearest  Pasteur  Institute  for  treatment. 


168  BACTERIOLOGY   FOR   NURSES 

When  any  doubt  exists  concerning  the  rabid  condi- 
tion of  the  animal,  it  is  never  killed,  but  kept  for 
observation,  as  a  diagnosis  after  death  is  often 
impossible. 

In  the  statistics  of  the  Pasteur  Institute  of  Paris 
it  is  shown  that  in  1886  there  were  2671  persons 
treated,  with  25  deaths ;  and  in  1898  there  were 
1465  persons  treated,  with  3  deaths. 

SCARLET  FEVER 

Scarlet  fever  is  an  acute  fever,  accompanied  by  a 
diffused,  vivid  scarlet  rash  from  which  it  derives 
its  name,  and  by  throat  complications,  varying  from 
a  simple  sore  throat  to  a  serious  diphtheritic  infection. 
The  organism  which  causes  scarlet  fever  is  still  un- 
known, although  many  years  of  research  have  been 
devoted  to  the  subject  by  bacteriologists  in  all  parts 
of  the  world.  Secondary  infections  of  streptococci 
are  very  common  in  scarlet  fever. 

The  sources  of  infection  in  scarlet  fever  are  still 
disputed  points,  while  there  is  probably  no  doubt  that 
infectious  particles  are  projected  from  the  mouth  and 
nose  by  the  acts  of  sneezing  and  coughing,  the  former 
theory  that  the  peeling  epidermis  was  the  chief  source 
of  danger  is  no  longer  held  by  the  best  authorities. 

Rigid  quarantine,  with  scrupulous  disinfection  of 


YELLOW    FEVER  169 

everything  contained  in  the  sick  room,  are  the  best 
prophylactic  measures  to  be  employed. 

Measles,  mumps,  and  whooping  cough  are  all 
infectious  diseases  of  childhood  of  unknown  origin. 
In  family  life  isolation  is  rarely  enforced,  as  the 
diseases  are  so  highly  contagious  that  room  quaran- 
tine is  not  usually  effective.  In  hospitals,  where 
better  facilities  for  isolation  are  found,  rigid  quaran- 
tine is  always  observed. 

YELLOW  FEVER 

Yellow  fever  is  an  infectious  fever  characterized 
by  a  high  temperature,  great  prostration,  vomiting 
of  mucus,  followed  by  bile  ("  black  vomit  "),  dimin- 
ished secretion  of  urine,  and  albuminuria.  The  fa- 
talities are  very  high,  ranging  from  35  per  cent  to 
99  per  cent  in  different  epidemics. 

The  disease  is  endemic  in  the  West  Indies,  in 
Brazil,  and  in  West  Africa,  from  which  it  is  sometimes 
carried  into  neighboring  countries,  resulting  in  ter- 
rible epidemics  which  are  only  controlled  by  the 
advent  of  frost. 

No  organism  has  yet  been  proven  to  be  the  cause 
of  yellow  fever,  although  there  seems  to  be  no  doubt 
that  the  disease  is  due  to  an  ultra-microscopic  germ 
which  is  contained  in  the  blood  of  the  infected  person. 


170  BACTERIOLOGY   FOR   NURSES 

The  disease  has  been  reproduced  by  the  injection 
of  a  portion  of  blood,  taken  from  a  yellow-fever 
patient,  into  a  susceptible  person. 

For  centuries  it  was  supposed  that  the  disease  was 
carried  by  contact.  In  1900,  following  the  Spanish- 
American  War,  a  United  States  Army  Commission 
was  appointed  to  investigate  the  cause  and  modes 
of  transmission  of  yellow  fever,  which  resulted  in 
finding  proof  of  the  method  of  infection,  although 
the  cause  is  still  unknown. 

Several  years  prior  to  1900,  Dr.  Carlos  Finlay  of 
Havana  had  advanced  the  theory  that  yellow-fever 
infection  is  carried  by  mosquitoes,  and  taking  this 
theory  as  a  basis  the  Commission  proved  without 
question  that  infection  is  carried  only  by  a  certain 
species  of  mosquito,  Stegomyia  fasciata,  in  the  same 
manner  as  the  Anopheles  carries  the  parasite  of  ma- 
laria. The  doctors  of  the  Commission  reared  the 
mosquitoes  from  eggs,  and  then  allowed  them  to 
bite  yellow-fever  patients,  and  later  to  bite  non-im- 
munes  who  had  been  quarantined  and  could  not  pos- 
sibly have  contracted  yellow  fever  in  any  other  way. 
Of  twelve  non-immunes  ten  contracted  yellow  fever. 

In  later  experiments  seven  men  lived  for  twenty 
days  in  a  mosquito-proof  house ;  these  men  slept  in 
the  soiled  garments  of  yellow-fever  patients,  but  no 


YELLOW    FEVER  171 

infection  followed,  showing  conclusively  that  the 
disease  can  be  contracted  only  by  the  bite  of  the 
mosquito,  Stegomyia  fasciata. 

In  Havana,  Cuba,  during  the  year  1900-1901,  the 
yellow-fever  cases  numbered  1240  and  the  deaths 
305.  In  the  following  year,  1901-1902,  there  were 
31  cases  and  6  deaths. 

Typhus  fever,  which  resembles  Rocky  Mountain 
spotted  fever  in  some  respects,  is  thought  to  be 
identical  with  Mexican  tabardillo ;  it  is  also  shown 
that '"Brill's  disease"  is  a  form  of  typhus  infec- 
tion. The  specific  germ  has  not  been  isolated. 
The  disease  may  be  transmitted  by  the  bite  of  the 
louse,  and  possibly  by  the  bite  of  the  flea  and  the 
bedbug. 

Rocky  Mountain  Spotted  Fever.  —  This  disease 
as  far  as  is  known  is  confined  to  the  Bitter  Root 
Valley  of  Montana  and  the  neighboring  mountains, 
and  is  transmitted  by  ticks.  The  germ  has  not  been 
isolated. 

Epidemic  Infantile  Paralysis.  —  Although  it  has 
been  known  for  fifty  years  that  this  disease  is 
infectious  and  carried  from  one  person  to  another 
by  contact,  presumably  in  the  nasal  discharges, 
the  microorganism  has  not  been  isolated. 


CHAPTER  XVII 

BACTERIA   IN   AIR,    SOIL,    WATER,    AND  POOD 

THE  presence  of  bacteria  in  air,  in  soil,  in  water, 
and  in  foods  is  constant,  and  under  favorable  con- 
ditions for  their  growth  and  multiplication  may 
become  a  serious  menace  to  health. 

In  air  bacteria  may  always  be  found  upon  the 
floating  dust,  the  largest  number  occurring  in 
crowded  dwellings  and  in  the  air  nearest  to  the 
surface  of  the  earth  in  cities.  In  the  higher  altitudes, 
as  in  the  mountains,  the  number  of  bacteria  de- 
creases with  the  altitude. 

It  is  not  only  when  the  bacteria  in  the  air  belong  to 
the  disease-producing  class  that  they  constitute  a 
source  of  danger,  for  the  action  of  the  bacteria  con- 
cerned in  the  process  of  decomposition  and  putre- 
faction may  be  particularly  dangerous  in  foods,  and 
must  be  especially  considered  in  the  care  of  foods. 

The  theory  of  "  air-borne "  infection  being 
much  disputed,  has  largely  been  supplanted  by  the 

172 


BACTERIA   IN   AIR,    SOIL,    WATER,    AND   FOOD      173 

proofs  of  the  greater  frequency  of  "  contact  "  in- 
fection. 

In  Soil.  —  Besides  the  saprophytes  which  grow  and 
multiply  in  the  soil,  and  are  necessary  to  the  soil  and 
to  the  higher  plants,  there  are  several  pathogenic 
bacteria  which  find  favorable  resting  places  in  the 
soil,  notably  tetanus,  and  typhoid-fever  bacilli, 
and  the  spirilla  of  Asiatic  cholera. 

Cultivated  garden  soil,  which  is  frequently  ferti- 
lized, shows  the  greatest  number  of  bacteria,  owing  to 
the  presence  of  dead  organic  material,  and  sandy  soil 
the  least.  In  favorable  soils  bacteria  may  be  found 
to  the  depth  of  four  or  five  feet  in  the  soil. 

Wherever  filth  of  any  kind,  as  manure,  sewage,  and 
decaying  vegetation,  is  deposited  in  or  upon  the  soil, 
pathogenic  bacteria  are  usually  found.  Their  growth 
and  multiplication  in  the  soil  is  still  a  disputed  ques- 
tion, although  typhoid  bacilli  and  the  spores  of 
tetanus  may  survive  and  retain  their  virulence  for 
many  months  in  soil  containing  large  quantities  of 
organic  matter,  such  as  would  be  found  in  a  garden. 
Experiments  have  proven,  however,  that  in  time 
the  soil  bacteria  will  overcome  the  disease-producing 
organisms,  or  in  other  words  the  soil  purifies  itself. 

In  Water.  —  Water  outside  of  the  laboratory  is 
never  free  from  bacteria,  although  most  of  them  are 


174  BACTERIOLOGY   FOR   NURSES 

harmless  to  man,  unless  present  in  extraordinary 
numbers. 

The  appearance  of  water  cannot  be  a  guide  for  its 
purity,  neither  are  the  odor  or  flavor  any  indication  of 
its  real  condition.  It  is  conceded  that  the  only  way 
by  which  the  purity  of  water  may  be  determined  is 
by  bacteriological  examination. 

Surface  drainage  and  sewage  are  the  most  common 
sources  of  water  pollution;  both  carry  enormous 
quantities  of  organic  matter,  including  human  ex- 
creta, which  is  always  particularly  dangerous,  into 
wells  and  other  sources  of  water  supply,  and  both  are 
very  likely  to  contain  many  pathogenic  bacteria. 

Polluted  water  carries  infection  by  its  use  as 
drinking  water,  or  by  its  use  for  washing  dishes,  or 
by  its  use  for  cleaning  foods  which  are  eaten  without 
cooking,  such  as  celery,  lettuce,  radishes,  tomatoes, 
and  many  fruits.  For  domestic  use,  filtration  with  a 
proper  filter  or  boiling  for  ten  minutes  are  the  best 
methods  of  purifying  water.  In  large  cities  sand 
nitration  is  employed  to  free  the  water  from  bacteria; 
a  well-managed  sand  filter  will  or  should  hold  back 
98  per  cent  of  the  bacteria. 

In  Food.  —  The  bacteria  which,  by  their  activities, 
cause  the  decomposition  and  putrefaction  of  dead 
organic  matter  are  to  be  reckoned  with  in  every 


BACTERIA    IN    AIR,    SOIL,    WATER,    AND   FOOD      175 

household  in  the  care  of  food  supplies.  For  this 
reason  food  is  kept  at  a  low  temperature  to  prevent 
bacterial  growth,  and  to  preserve  food  for  any 
length  of  time  it  is  sterilized  and  sealed  while  boiling 
hot.  Besides  sterilization  and  low  temperature, 
perfect  cleanliness  is  the  most  important  measure  to 
be  employed  against  the  invasion  of  bacteria  and  its 
resulting  decomposition.  Unclean  utensils,  dish  tow- 
els, and  ice  boxes  will  infect  the  best  food  materials 
very  quickly,  and  are  no  doubt  the  indirect  cause  of 
many  causes  of  food  poisoning  which  we  call  "pto- 
main-poisoning. ' ' 

Unclean  methods  of  handling  meat,  fish,  and  milk 
are  particularly  favorable  to  the  development  of 
bacteria  which  produce  highly  poisonous  substances. 

Bacteria  are  found  in  all  milk,  the  amount  varying 
with  the  cleanliness  of  the  cow,  of  the  stable,  of  the 
utensils,  of  the  milker,  and  all  other  persons  who  may 
handle  it.  Pathogenic  bacteria  are  often  found  in 
milk,  and  may  come  from  a  diseased  cow,  from  a 
diseased  milker,  from  polluted  water  used  upon 
utensils,  or  from  insects  which  often  carry  infectious 
materials  upon  their  feet  and  bodies;  in  fact,  the 
ways  of  handling  milk  from  the  cow  to  the  consumer 
take  it  through  so  many  hands,  utensils,  and  varia- 
tions of  temperature  that  infection  through  milk 


176  BACTERIOLOGY   FOR   NURSES 

is  extremely  common,  and  at  the  same  time  it  fur- 
nishes one  of  the  most  favorable  media  for  the  growth 
and  multiplication  of  bacteria  of  all  kinds. 

Many  large  cities  have  established  a  system  of 
milk  inspection  which  rejects  milk  containing  over  a 
certain  number  of  bacteria,  thus  recognizing  that 
milk  is  one  of  the  most  important  articles  of  food  in 
common  use. 

Typhoid  fever,  diphtheria,  scarlet  fever,  tubercu- 
losis, and  infantile  diarrhoeas  and  gastric  disorders 
are  largely  disseminated  by  means  of  impure  milk. 

Cleanliness  is  the  most  important  measure  used  for 
controlling  the  infection  of  milk;  while  " Pasteuriz- 
ing" by  heating  to  60°  C.  (140°  F.)  for  twenty 
minutes  will  destroy  any  ordinary  bacteria  which 
milk  may  contain. 

The  action  of  all  bacteria  upon  food  materials  is 
not  however  to  its  detriment;  in  many  articles  of 
food,  such  as  butter,  cheese,  and  other  milk  products, 
vinegars,  wines,  etc.,  the  activities  of  certain  bacteria 
are  necessary  for  their  flavor  or  aroma. 

In  several  industries,  as  the  tanning  of  hides  for 
leather,  and  in  the  preparation  of  flax  for  linen,  bac- 
terial activity  forms  an  important  part  of  the  process. 


INDEX 


Acid,  production  of,  11,  44. 
Acid-proof  bacteria,  87. 
Actinomyces,  102. 
Actinomycosis,  102. 
Adaptability  of  bacteria,  30. 
Aerobes,  29. 
Agar,  25. 
Agglutinins,  65. 
Alexin,  60. 

Alkali,  production  of,  44. 
Anaerobes,  29. 
Animal  inoculation,  26. 
Anopheles,  159. 
Anthrax,  104. 
Antibodies,  65. 
Antiseptics,  34. 
Antitoxin,  57,  121,  132. 
Asiatic  cholera,  147. 
Attenuation,  56. 
Autoclave,  21. 

Bacillus,  9. 

anthracis,  104. 

botulinus,  134. 

chauvei,  133. 

coli,  108. 

diphtheria?,  117. 

influenza?,  134. 

Klebs-Loffler,  117. 

Koch- Weeks,  137. 

leprse,  97. 

mallei,  100. 

pestis,  137. 

pneumonia?,  71. 

psittacosis,  108. 

tetami,  126. 

tuberculosis,  86. 

typhosus,  109. 

Welchii,  133. 
Bacteremia,  49. 
Bacteria,  adaptability  of,  J 

and  disease,  46. 


chemical  composition  of,  13. 

discovery  of,  1. 

effects  of  chemicals  upon,  33. 

effects  produced  by,  43. 

in  soil,  32,  173. 

methods  of  study,  15. 

structure  and  development,  9,  10, 
Black  death,  137. 
Bovine  tuberculosis,  89. 
Bubonic  plague,  137. 

Carbolic  acid,  36. 
Carbol-soap,  38. 
Cholera,  147. 
Coccus,  9. 
Colonies,  12. 

Colon-typhoid  bacilli  group,  108, 
Copper  sulphate,  36. 
Corrosive  sublimate,  36. 
Crenosol,  37. 
Creolin,  37. 
Culture-media,  19,  25. 
tubes,  24. 

Diphtheria,  117. 

antitoxin,  57,  121. 
Diplococcus  pneumonias,  71. 
Disinfectants,  34,  40. 
Dysentery,  155. 

Endotoxins,  45. 
Entamceba  histolytica,  156. 
Enteritis,  108. 
Enzymes,  43. 

Epidemic  cerebro-spinal  meningitis, 
74. 

Farcy,  101. 
Fermentation,  44. 
Flagella,  9. 

Food,  for  bacteria,  30. 
Foot-and-mouth  disease,  47. 

177 


178 


INDEX 


Formaldehyde,  39. 
Frankel's  pneumococcus,  71. 

Gas  production,  44. 
Gelatin,  18. 
Glanders,  100. 
Glassware,  23. 
Gonococcus,  76. 
Gonorrhoea,  76. 

Hay  bacillus,  10. 
Hydrophobia,  165. 

Immunity,  54. 

active,  55. 

passive,  55. 
Inflammation,  66. 
Influenza,  134. 
Infusoria,  3. 
Involution  forms,  9. 

Klebs-Loffler  bacillus,  117. 
Koch- Weeks  bacillus,  137. 

Leprosy,  97. 
Light,  28. 
Lysol,  37. 

Malaria,  158. 
Malignant  edema,  133. 

pustule,  106. 
Mallein,  102. 
Measles,  169 
Meningitis,  74. 
Meningococcus,  74. 
Microscopic  methods,  26. 
Milk,  as  a  culture  medium,  113. 
Mixed  infections,  50. 
Moisture,  effects  of,  29. 
Morphology,  of  bacteria,  7. 
Motility,  9. 

Nitrifying  bacteria,  32. 
Nucleus,  9. 

Opsonic  index,  62. 
Opsonins,  62. 
Otitis  media,  68. 
Oxygen,  29. 

Parasites,  30. 
Phagocytosis,  61. 
Phosphorescence,  43. 


Photogenic  bacteria,  43. 

Pigment,  44. 

Plague,  137. 

Plasmodium  malariae,  158. 

Pneumococcus,  71. 

Pneumonia,  66,  71. 

Potassium  permanganate,  35. 

Preservation  of  foods,  174. 

Protozoa,  155. 

Pseudo-diphtheria  bacillus,  125. 

Ptomains,  44. 

Pure  culture,   methods  of  obtain 

ing,  5,  18. 
Putrefaction,  43. 
Pyemia,  67. 

Rabies,  165. 
Relapsing  fever,  154. 

Saprophytes,  31. 
Sarcinse,  10. 
Scarlet  fever,  168. 
Septicaemia,  49,  67. 
Sleeping  sickness,  157. 
Smallpox,  162. 
Soap,  37. 
Spirillum,  9. 

cholerae,  147. 

obermeieri,  154. 
Spirochseta  pallida,  81. 
Spontaneous  generation,  4. 
Spores,  11. 
Sporozoa,  155. 
Staining,  25. 
Staphylococcus,  67. 

albus,  67. 

aureus,  67. 
Sterilization,  20. 

by  heat,  20. 

by  chemicals,  20. 

discontinuous,  21. 
Sterilizer,  hot  air,  20. 

Arnold's,  22. 
Streptococcus,  68. 
Sulphur  dioxide,  35. 
Suppuration,  66. 
Susceptibility,  54. 
Syphilis,  80. 

Tanning,  176. 
Temperature  relations,  27. 
Tetanus,  126. 


INDEX 


179 


Thermal  death  point,  28. 
Thermogenic  bacteria,  43. 
Tick,  157. 
Toxaemia,  49. 
Toxins,  44,  12G. 
Transmission  of  infection,  51. 
Treponema  pallidum,  81. 
Trypanosomes,  157. 
Tsetse-fly  disease,  157. 
Tuberculin,  96. 
Tuberculosis,  85. 
Typhoid  fever,  108. 


Ulcerative  endocarditis,  68. 


Vaccination,  116,  152,  163. 
Venereal  diseases,  76. 
Virulence,  48,  66. 

Whooping  cough,  169. 
Widal  reaction,  65,  115. 

Yellow  fever,  169. 


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Cloth,  339  pp.,  index,  izmo,  $1.75 

The  Medical  Times  says:  "After  reading  a  great  variety  of  trash  on  the  subject  of 
sexual  education  of  the  boys  and  girls  of  this  generation,  it  is  a  pleasure  to  have  the  sub- 
ject taken  up  in  a  frank,  open,  dignified  manner  by  Dr.  Moll.  He  leads  one  through  the 
mazes  of  the  sexual  development  of  the  child,  and  so  cleverly  analyzes  its  real  feelings 
that  one  instinctively  feels  one's  self  well  qualified  to  interpret  child  psychology  and  to 
apply  the  lessons  gained  therefrom." 

The  Care  of  the  Body 

BY  R.   S.  WOODWORTH, 

PROFESSOR   IN   COLUMBIA    UNIVERSITY 

Cloth,  359  pp.,  index,  I2mo,  $1.50 

The  blood,  the  circulation,  breathing,  food,  digestion,  wastes  and  their  removal,  diet, 
bodily  heat,  the  work  of  the  body,  the  ear,  the  eye,  nerve  and  brain,  work,  rest,  and 
recreation,  indulgences,  the  cycle  of  life  and  disease,  are  among  the  different  topics 
which  the  author  takes  up. 


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ANEW  IMPORTANT  BOOK  FOR  NURSES 

Materia  Medica  for  Nurses 

BY  A.  S.  BLUMGARTEN,  M.D. 

INSTRUCTOR   IN   MATERIA   MEDICA   AT  THE  GERMAN    HOSPITAL  TRAINING 
SCHOOL  FOR   NURSES,  NEW  YORK. 

8vo,  ill. 

This  book  is  unique,  as  it  is  planned  along  lines 
not  before  attempted.  It  is  in  plain,  simple  English, 
intensely  interesting  in  style,  and  is  written  along  strictly 
pedagogic  lines.  It  therefore  contains  clear,  concise  in- 
struction throughout.  Stress  has  been  laid  upon  teaching 
facts,  not  words,  with  the  result  that,  while  thoroughly 
scientific,  the  book  is  free  from  the  technical  terminology 
in  which  seems  to  lie  the  fault  of  so  many  text-books 
for  nurses. 

It  will  assist  and  train  the  nurse  in  the  observation 
of  the  effects  of  drugs  as  produced  upon  actual  patients 
in  the  wards.  The  physiological  action  is  particularly 
arranged  to  facilitate  the  retention  of  the  facts  pre- 
sented. A  special  feature  will  be  found  in  an  original 
and  very  elaborate  chapter  on  "  Solutions."  It  enables 
the  nurse  to  handle  any  problem  in  the  calculation  and 
administration  of  a  required  dose  of  a  drug,  or  to  make 
up  any  required  solution.  There  is  also  a  chapter  on 
"  Prescription  Reading,"  and  there  are  numerous  tables 
such  as  "Saturation  Points,"  "Comparative  Action  of 
Various  Drugs,"  etc.,  scattered  throughout  the  text.  It 
also  contains  all  the  new  and  non-official  remedies  in 
common  use. 


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Publishers          64-66  Fifth  Avenue  New  York 


IMPORTANT  BOOKS  FOR  NURSES 

Primary  Nursing  Technique  for  First  Year  Pupil  Nurses 
BY  ISABEL  McISAAC. 

Cloth,  izmo,  197  pp.,  $1.25 

A  thoroughly  honest  book  for  nurses  starting  on  their  course  of  study.  It  is  written 
with  the  one  object  in  view  of  inculcating  in  the  minds  of  its  readers  the  fact  that  an 
accurate  knowledge  of  the  human  body  is  the  first  essential  to  successful  nursing. 

Hygiene  for  Nurses 

BY   ISABEL   McISAAC. 

Cloth,  izmo,  208  pp.,  $1.2 5 

The  pages  of  this  book  are  full  of  just  the  information  that  every  woman  in  charge  of 
souls  and  bodies  needs.  The  chapters  on  food,  ventilation,  sewage,  causes  and  dissemina- 
tion of  disease,  household,  personal  and  school  hygiene,  the  hygiene  of  occupation,  disin- 
fection, etc.,  are  all  of  the  most  vital  interest  and  should  be  taken  to  heart  by  every  one. 

Text-Book  of  Anatomy  and   Physiology  for  Nurses 
BY  DIANA   C.    KIMBER. 

FORMERLY     ASSISTANT     SUPERINTENDENT,     NEW     YORK     CITY     TRAINING 
SCHOOL   FOR    NURSES,  BLACKWELL'S   ISLAND,   N.Y. 

Third  edition  revised  by  Caroline  E.  Gray,  R.N.,  Assistant  Superintendent, 
New  York  City  Training  School  for  Nurses. 

Cloth,  8vo,  438  pp.,  ill.,  $2.50 

"  From  her  long  experience  in  teaching  classes  the  author  knows  exactly  what  nurses 
need  and  how  much  can  be  reasonably  given  them  in  the  short  space  of  two  years'  time, 
and  for  the  assistance  of  the  inexperienced  teacher  her  book  is  arranged  in  lessons  cov- 
ering the  first  or  junior  year.  The  subjects  are  presented  with  sincerity  and  distinction, 
and  illustrated  by  cuts  and  plates  of  unusual  merit."  —  The  Trained  Nurse. 

Home  Nursing 

BY  ISABEL   MAcDONALD. 

Cloth,  326  pp.,  izmo,  $0.80 

Miss  MacDonald,  in  her  Preface  to  this  admirable  and  most  useful  book  on  Home 
Nursing,  expresses  her  belief  that  "  there  is  room  for  a  work  written  in  simple  language 
and  showing  more  fully  than  is  possible  in  a  lecture  how  to  alleviate  pain  and  discom- 
fort, how  to  avoid  pitfalls  and  mistakes,  and  how  to  help  in  saving  valuable  lives  in  times 
of  sickness  and  danger." 

District  Nursing 

BY   MABEL  JACQUES. 
With  an  Introduction  by  Dr.  John  H.  Pryor. 

Cloth,  ismo,  $1.00          by  mail  $1.08 

Fhe  writer  has  given  us  a  book  that  is  practical  and  useful,  and  one  which  will  prove 
-  great  help  to  all  who  take  an  active,  personal  share  in  social  advance. 


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The  Treatment  of  Fractures  by  Mobolization  and  Massage 
BY  JAMES   B.    MENNELL, 

HOUSE  SURGEON  AND  CASUALTY  ASSISTANT,  ST.  THOMAS*  HOSPITAL,  LONDON.  WITH 
AN  INTRODUCTION  BY  DR.  LUCAS-CHAMPONNIERE,  CHIRURGIEN  HONORAIRE  DE  L'HOTEL 
DIEU,  MEMBRE  DE  L'ACADEMIE  DE  MEDICINE,  PRESIDENT  DE  LA  SOCIETE  INTER- 
NATIONALE DE  CHIRURGIE,  ETC. 

Cloth,  8w,  458  pp.,  ill.,  $3.00 

Dr.  Mennell  has  made  his  work  a  practical,  rather  than  a  pathological,  treatment  of 
fractures  by  methods  which,  although  well  known  on  the  Continent,  have  as  yet  been 
little  used  in  America  and  England. 

Dr.  Mennell's  success  in  this  method  of  treatment  of  fractures  has  been  marked  and 
his  experience  has  been  ample.  His  ideas  are  revolutionary  but  are  worthy  of  very  seri- 
ous consideration,  and  we  would  strongly  urge  every  physician  who  has  occasion  to 
reduce  fractures  to  read  this  book. 

Mind  and  Health 

BY   EDWARD   E.   WEAVER,  PH.D. 

Cloth,  500  pp.,  i2mo,  $2.00 

This  treatise  is  an  attempt  to  embody  some  of  the  latest  results  of  the  psychological 
study  of  the  influence  of  mental  states  upon  health.  After  a  thorough  psychological 
discussion,  a  painstaking  examination  is  made  of  various  systems  of  healing  of  a  reli- 
gious character  from  the  standpoint  of  present-day  scientific  mental  healing.  Both  the 
strong  points  and  weaknesses  of  these  systems  are  pointed  out. 


The  People's  Medical  Guide 


Points  for  the  Patient,  Notes  for  the  Nurse,  Matter  for  the  Medical  Adviser,  Succor  for 
the  Sufferer,  Precepts  for  the  Public. 

BY  JOHN   GRIMSHAW,   M.D. 

B.S.  (LOND.),  D.P.H.  (CAMB.),  M.R  c.s.  (ENG.),  ETC. 

Cloth,  839  pp.,  index,  glossary,  ill.,  8w,  $3.00 

A  medical  guide  for  the  people,  thoroughly  modern  in  matter  and  tone,  embracing  all 
the  remarkable  advances  of  the  last  decade.  Besides  constituting  a  plea  for  a  reform  in 
medical  education,  this  book  is  an  exposition  of  the  different  branches  of  medical  work 
and  social  reform. 

Biological  Aspects  of  Human  Problems 

BY  CHRISTIAN   A.    HERTER,   M.D. 

LATE   PROFESSOR   OF   PHARMACOLOGY  AND   THERAPEUTICS   IN   COLUMBIA   UNIVERSITY 

Cloth,  344  pp.,  I2mo.,  $1.50 

This  work  gives  the  personal  convictions  of  a  foremost  authority  on  the  far-reaching 
effects  of  Biology.  Dr.  Herter  first  discusses  in  what  respects  the  animal  body  may  be 
regarded  as  a  mechanism,  next  he  treats  of  the  nature  of  the  self-preservative  and  sex- 
ual instincts  which  appear  to  be  the  most  fundamental  of  all  instinctive  qualities  in 
living  protoplasm.  Following  this  the  various  instincts  of  human  nature,  such  as  those 
which  relate  to  imitation,  affection,  love  of  beauty,  the  awe  of  the  powerful  and  unin- 
telligible, are  taken  up,  while  finally  the  tendencies  in  development  in  education,  litera- 
ture, music,  art,  business,  politics  and  science,  are  considered.  There  has  been  no  saner 
exposition  of  the  essential  duties  of  life. 


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' '  We  have  no  hesitation  in  saying  that  this  work  will  live  as  one  of  the  greatest 
biographies  in  the  English  language."  —  The  Daily  Chronicle,  London. 


The  Life  of  Florence  Nightingale 

By  SIR    EDWARD    COOK 

WITH  PHOTOGRAVURE  PORTRAITS 

Two  volumes.     Cloth,  8vo,  $7.50 

"This  book,"  says  the  author  in  his  Introductory  remarks  to  this  notable 
biography,  "is  not  a  history  of  the  Crimean  War,  nor  of  nursing,  nor  of  In- 
dian administration.  Something-on  all  these  matters  will  be  found  in  it ;  but 
only  so  much  of  detail  as  was  necessary  to  place  Miss  Nightingale's  work  in 
its  true  light  and  to  exhibit  her  characteristic  methods.  So,  also,  manv  other 
persons  will  pass  across  the  stage  —  persons  drawn  from  many  different 
classes,  occupations,  walks  in  life  ;  but  the  book  does  not  aim  at  giving  a 
detailed  picture  of '  Miss  Nightingale's  circle.'  Her  relations,  her  friends,  her 
acquaintances,  her  correspondents  only  concern  us  here  in  so  far  as  their  deal- 
ings with  her  affected  her  work,  or  illustrate  her  character." 

The  biography  is  in  two  volumes  and  is  divided  into  seven  Parts.  Part  I 
tells  the  story  of  Florence  Nightingale's  early  years  and  her  early  aspirations 
for  a  life  of  active  usefulness.  Part  II  is  devoted  to  the  Crimean  War,  where 
it  was  as  Administrator  and  Reformer  rather  than  as  the  Ministering  Angel  — 
the  Lady  with  the  Lamp  —  that  her  peculiar  powers  were  shown.  Part  III  por- 
trays her  laying  her  plans  for  the  health  of  the  British  Soldier  —  the  period  of 
her  close  cooperation  with  Sidney  Herbert.  Part  IV  describes,  as  its  main 
themes,  the  work  she  did  as  Hospital  Reformer  and  the  Founder  of  Modern 
Nursing.  Part  V  deals  with  a  new  interest  in  her  life  and  a  new  sphere  of  her 
work.  Her  efforts  on  behalf  of  the  British  Soldier  at  home  led  to  a  like 
attempt  for  the  army  in  India.  Then  gradually  she  was  drawn  into  other  ques- 
tions, till  she  became  a  keen  Indian  reformer  all  along  the  line.  Part  VI 
continues  this  subject,  and  introduces  another  sphere  in  which  her  influence 
had  important  significance,  namely,  the  reform  of  the  Workhouse  Nursing ; 
and  as  one  thing  led  to  another  it  will  be  seen  that  Florence  Nightingale  de- 
serves also  to  be  remembered  as  a  Poor  Law  Reformer.  Part  VII  comprises 
the  last  thirty-eight  years  of  her  life  —  a  period  which,  though  it  has  admitted 
of  more  summary  treatment,  was  full  of  interest.  It  deals  with  her  literary 
work  and  her  studies  in  Plato  and  Christian  Mystics.  An  endeavor  is  made 
to  portray  her  as  the  "Mother-Chief"  (as  she  was  called}  of  the  nurses.  It 
describes  other  of  her  projects  and  realizations,  and  so  brings  the  long  and 
wonderful  life  to  a  close. 

It  should  be  pointed  out  that  for  the  purposes  of  this  work  Sir  Edward 
Cook  has  had  access  to  the  family  papers,  and  has  therefore  been  able  to  pre- 
pare the  first  full  and  authentic  record  of  Florence  Nightingale's  character  and 
career.  The  volumes  are  rendered  additionally  attractive  by  the  inclusion  of 
several  interesting  portraits. 

"  A  masterly  biography  which  not  only  puts  into  a  permanent  record  her  whole-souled  de- 
votion and  humanity,  but  relates  the  history  of  one  of  the  greatest  and  most  fruitful  move- 
ments of  modern  time.  For  as  Sir  Edward  well  says,  her  nursing  mission  in  the  Crimean  War 
was  only  the  starting  point.  .  .  .  He  has  put  the  essence  of  saintliness  into  good  literature 
and  sober  history."—  The  Pall  Mall  Gazette. 

"  A  noble  biography."  —  The  Daily  News,  London. 


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This  book  is  DUE  on  the  last  date  stamped  below 


3(3  1  937 
4 


Form  L-9-15rn-7,'31 


AUG  I'1 1943 
DEC  1 2  1944 

UN  171950 

1  APR  2  8 13ks 


46        Mclsaac   - 


for  nurses. 


